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## Trevor is pulling his younger brother in a wagon. He pulls the wagon 50 m to the corner with a force that is a parallel with the ground. He then turns the wagon around and pulls it 50 m back to the starting point with the same force at an angle of 30 degrees with respect to the ground. How does the amount of work Trevor performs going to the corner compare with the amount of work he performs coming back? A) they are the same because he uses the same amount of force B) they are the same because he travels the same distance C) he does less work coming back because the force moving the wagon is only 50cos30 D)he does more work coming back because the force moving the wagon is only 50cos60

Work has the greatest value when the force done is
parallel to the direction of motion. In this case, the work done in pulling the
wagon to the corner is greater than the amount of work done in pulling the
wagon back to the starting point. This is because an angle of 30 degrees is
applied when pulling it back. The formula for work when angle is applied is:

Wx = W cos θ

Where in this case, θ = 30

Therefore,
the answer to this is letter:

C) he does less work coming back because the force moving
the wagon is only 50cos30

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## The main difference between gases and liquids is that in gases A.the molecules are moving faster b.the forces between molecules are greater c.the distance between molecules are greater d.the molecules collide more frequently

The main difference between gases and liquids is that in gases A.the molecules are moving faster b.the forces between molecules are greater c.the distance between molecules are greater d.the molecules collide more frequently

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## How fast do you think the air particles in this room are moving compared to a 50mph car

How fast do you think the air particles in this room are moving compared to a 50mph car

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## A 0.023 kg beetle is sitting on a record player 0.15 m from the center of the record. If it takes 0.070 N of force to keep the beetle moving in a circle on the record, what is the tangential speed of the beetle?

0.68 m/s

Explanation:

The centripetal force that keeps the beetle moving in circle is given by:

where

m is the mass of the beetle

v is the tangential speed of the beetle

r is the distance of the beetle from the center of the record

In this problem, we know the force (F=0.070 N), the mass of the beetle (m=0.023 kg) and the distance from the center (r=0.15 m), therefore we can re-arrange the equation to find the tangential speed:

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## The type of carbohydrate that is useful in moving waste through the body system is:

The type of carbohydrate that is useful in moving waste through the body system is FIBER.  Fiber is a type of carbohydrate that passes through the body undigested.
Fiber is very important to be part of the diet because it
helps regulate the body’s use of sugars, helps to keep hunger and blood sugar in check.
Children and adults need at least 20 to 30 grams of fiber per day for good health
Dietary fibers are found in fruits, vegetables and whole grains.

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## What can you expect from moving 5500 feet higher?

What can you expect from moving 5500 feet higher?

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## Kathleen is in labor and is told by her physician that the baby's feet, rather than his head, are moving down the birth canal first. what type of delivery is likely to be performed

Kathleen is in labor and is told by her physician that the baby’s feet, rather than his head, are moving down the birth canal first. what type of delivery is likely to be performed

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## A 0.023 kg beetle is sitting on a record player 0.15 m from the center of the record. if it takes 0.070 n of force to keep the beetle moving in a circle on the record, what is the tangential speed of the beetle? 0.68 m/s 0.46 m/s 0.33 m/s 0.11 m/s

Tangential speed is 0.68 m/s

Explanation:

It is given that,

Mass of the beetle, m = 0.023 kg

It is placed at a distance of 0.15 m from the center of record i.e. r = 0.15 m.

If it takes 0.070 n of force to keep the beetle moving in a circle on the record i.e. centripetal force acting on it is, F = 0.070 N

We have to find the tangential speed of the beetle. The formula for centripetal force is given by :

v is tangential speed

v = 0.675 m/s

or

v = 0.68 m/s

Hence, the correct option for tangential speed is (A).

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## A loaded moving truck is traveling 30 mph faster than a freight train. in the time it takes the train to travel 135 miles, the truck travels 225 miles. find the speed of the truck

Speed of truck= x
speed of train=x-30
A loaded moving truck is traveling 30 mph faster than a freight train. in the time it takes the train to travel 135 miles, the truck travels 225 miles. find the speed of the truck.

A loaded moving truck is traveling 30 mph faster than a freight train…
(x-30)=speed of train
the time it takes the train to travel 135 miles, the truck travels 225 miles…
135/(x-30)=225/x
the you multiply on both sides the x values and get…
135x=225x-6750
then you subtract 225x on both sides…
-90x=-6750
then you divide -90 on both sides…
x=75
the speed of the truck is 75mph
i hope this helped give me a thanks and a 5 star rating if it helped! c:

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## Which of the following will help prevent further shin split injury? A. changing to play on a hard surface B. resting until the discomfort goes away C. finishing by taking off your footwear D. moving more quickly to minimize the discomfort

The answer is B. resting until the discomfort goes away.
Other choices require further movement that may worsen the shin split.

The pain of the injury is triggered when a movement like running is done. The best way to lessen the pain is through resting. With this kind of condition, running is impossible to do. So it’s better to avoid foot regular movement and exercises. The best way to cure this is treatment from a doctor.

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## 6. What is a major corporation that includes a number of smaller companies in unrelated industries? a consumer mandate a franchise a conglomerate none of the above 7. What was “white flight”? middle-class white Americans leaving the cities for the suburbs rural poor moving to the cities middle-class white Americans leaving the suburbs for the cities urban poor moving to the country 8. In this case, the Supreme Court required criminal courts to provide free legal counsel to those who could not afford it. Gideon v. Wainwright Miranda v. Arizona Baker v. Carr Brown v. Board of Education 9. In 1896, in _______, the Supreme Court ruled that a Louisiana law requiring “separate but equal” public accommodations was constitutional. Sweatt v. Painter Plessy v. Ferguson Morgan v. Virginia Brown v. Board of Education of Topeka 10. Who gave the “I Have a Dream” speech during the march on Washington? A. Philip Randolph Robert Moses Martin Luther King, Jr. Bayard Rustin

Industrialization led to rising imperialism because
1) show of power: As one makes new technology, they would either want to test it out or show the other nations that what they produce is ground-breaking and the best. Usually if it is military technology, you would want to test it out, and with the use of “show of force”, can have people groups submit to your country.
2) Better technology: As technology advances, it usually makes something easier. In the case of imperialism, better military advances meant that they could (once again) have other people submit to you
3) Better transportation: This meant that you could take multiple countries at once, and can prove that you’re country is great by having supplies shipped over long distances to keep your troops up. If in need of more troops, you could send more.

hope this helps

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## Which is not a hazard that leads to injury A good posture B lack of assistance C moving to quickly d all of the above

Okay listen up people! I am vegan and if you go vegan, you will not lack anything! Most people believe that going vegan means you will be lacking in protein because of not eating meat but that’s not true. Many plants like avacadoes, beans, chickpeas, etc are very healthy sources of protein. Meat has protein in itself but it deteriorates the body. On the other hand, plant-based proteins are much healthier. So in other words, nothing is lacking when you go vegan and the benefits are priceless!

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## An object is moving north at a constant speed. A force of 5 N begins to push the object east at the same moment that a force of 5 N begins to push it west. What will happen to the object?

The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies.

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface.

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h.

So the time for the pencil and eraser to touch is T=1.3449 hours.

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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Natural Forces Affecting the Driver:

1. While the car stops, the person continues moving the way that the car were moving and then hits the obstacle in the car or the person can be thrown out of the vehicle. If the person wears belt, he will stop moving with the vehicle and won’t hit the obstacle.

2. We count approximate kinetic energy using the formula K = v^2. So the vehicle which is moving at 30 mph will have four times less kinetic energy than vehicle which is moving at 60 mph. If they have the same road conditions, the breaking distance will be four times as great for the car moving twice as fast.

3. Kinetic energy depends on object’s mass and velocity and it has direct relationship with the stopping distance. The lesser mass of the vehicle = the lesser kinetic energy and lesser stopping distance. => If both vehicles have the same velocity, then small vehicle has lesser kinetic energy than large vehicle.

4. We know that kinetic energy has this relationship with velocity K = v^2. So the best way to prepare to enter sharp curves in the roadway is to lower the speed. The most appropriate speed is 20-30 mph, but it depends on road conditions and car’s breaks condition.

5. Car crashes can happen with everyone so the best way is to be prepared. First the driver should wear a seatbelt while he’s driving. He should check his tires and breaks condition regularly. And also it’s important to slow down the vehicle while entering sharp curves. Without following these rules, the driver can get catastrophic injuries in a car crash.

Signs, Signals, and Pavement Markings:

1. It doesn’t matter where you go. All you need is to learn highway code. It’s very different to know the meanings of every road sign. Also, it’s necessary to check your car’s conditions and you should take some spare parts for your car in case of accidents. So wherever you go, it’s important to be prepared.

2. You should stop before crossing and take few minutes to make sure there is no train approaching. If there is no train approaching, you can pass a railroad crossing. If you see approaching train, you should wait until it will pass a railroad crossing.

3. You should stop before the lights and wait to check the traffic movement and signs. Make sure that everything is safe and pass the intersection. Don’t move fast to avoid accidents.

4. Flashing yellow light means that it’s not necessary to stop but you should to pay attention on the traffic movement. So it would be better to yield before the lights and make sure if it’s safe to move. After that you can cross the intersection.

5. The line change means that the lane changes and you can’t cross solid lines. Pay more attention on road marking because it shows how you should behave on the road or highway.

6. As you approach the next exit and  your passengers need to use the restroom and get some food, you should look for green signs which indicate food and rest stops. You should to slow down if you don’t want to skip the sign.

7. When you take the exit ramp off the expressway and merge onto the next road, you see yellow lines dividing the roadway which indicates that there is oncoming traffic and this is a two-way highway.

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## Enzo read this passage from “The Smithville Gazette: Neighborhood Thief Strikes Again.” Another episode in the recent spate of neighborhood thefts occurred on Saturday at Ferguson’s department store. Several pieces of jewelry were taken at approximately 12:30 in the afternoon. Mrs. Jane Dickson, the employee working the jewelry counter reported that she did not initially see the theft, but realized shortly before 1 p.m. that several necklaces were missing from inside the jewelry case, which she had accidentally left unlocked while moving away to help another customer. Instead of taking notes on the central idea, Enzo copied the passage down exactly. What is the best way to revise the passage into notes that reveal the central idea? a) Saturday @ 12:30 p.m., Ferguson’s, Mrs. Jane Dickson, jewelry, necklaces b) robbery @ Ferguson’s jewelry on Sat.—necklaces stolen c) On Saturday at Ferguson’s, there was a robbery and some jewelry was stolen. d) Mrs. Jane Dickson says there was a jewelry robbery.

Hey there!

Correct answer is D. Comma or Period Inside Rule

A. Question mark or exclamation point inside: those are not really necessary.

B. Colon or semicolon: not, a semicolon would divide the whole sentence and it would be shorten; a colon would work but after requested, when there is already a comma.

C. Question mark or Exclamation Point Outside Rule: would not work, becase it is an very polite and affirmative sentence.

D: A comma or period inside rule: actually, just a comma would work. Please, Cooper’s dad requested, go… Cooper’s dad requested must be in between commas as it is a vocative.

Hope this helps

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## Read the excerpt from Outcasts United. Luma pulled her Volkswagen Beetle into the center’s parking lot on a sunny June afternoon in 2004, before her team’s first tryouts. She wasn’t sure what kind of response her flyers had generated among the boys in the complexes around Clarkston. They were naturally wary. But on the other side of town, Jeremiah Ziaty had no doubt about his enthusiasm for the new team. His mother was still at work when he set out from the family’s apartment, a small backpack on his shoulder, ready to play. When Jeremiah arrived at the center, he joined twenty-two other boys on the small field behind the building. Which statement best describes how the author is developing the plot in this excerpt? – The author is describing two plots at the same time before moving on with the chronological order of the story. – The author is describing one plot of the story so he can move the events along chronologically. – The author is describing several plots at the same time to avoid telling the story in chronological order. – The author is describing one plot of the story but not moving the events along in chronological order.

Answer:  The correct answer is : When writing a research paper you should avoid: slang, first or second person, formality, contractions, jargon.

Explanation:    When writing this type of work should take into account the impersonality, not make too many subordinate sentences, use more nouns and verbs than adjectives and adverbs, use connectors when necessary, be accurate and precise, avoid metaphors, the text should be clear and understandable.

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## Select the statement that best describes how the forces relate.A. The object on which they are acting and the distance to that object determines the amount of force.B. nuclear and magnetic forces are different because magnetic forces are associated with unmoving charges, and weak nuclear forces are associated with moving charges.C. All forces are related to the mass of the object on which they are acting.The larger the mass, the weaker the forces become. D. Magnetic and electrical forces are similar because they are both related to the interactions between charged particles.

The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies.

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface.

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h.

So the time for the pencil and eraser to touch is T=1.3449 hours.

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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## Which sentences in this excerpt from Leo Tolstoy’s The Death of Ivan Ilyich show Ivan Ilyich’s struggle with his life and his inability to let go of his past? For three whole days, during which time did not exist for him, he struggled in that black sack into which he was being thrust by an invisible, resistless force. He struggled as a man condemned to death struggles in the hands of the executioner, knowing that he cannot save himself. And every moment he felt that despite all his efforts he was drawing nearer and nearer to what terrified him. He felt that his agony was due to his being thrust into that black hole and still more to his not being able to get right into it. He was hindered from getting into it by his conviction that his life had been a good one. That very justification of his life held him fast and prevented his moving forward, and it caused him most torment of all. Suddenly some force struck him in the chest and side, making it still harder to breathe, and he fell through the hole and there at the bottom was a light. What had happened to him was like the sensation one sometimes experiences in a railway carriage when one thinks one is going backwards while one is really going forwards and suddenly becomes aware of the real direction. “Yes, it was not the right thing,” he said to himself, “but that’s no matter. It can be done. But what is the right thing? he asked himself, and suddenly grew quiet.

Hey there!

Correct answer is D. Comma or Period Inside Rule

A. Question mark or exclamation point inside: those are not really necessary.

B. Colon or semicolon: not, a semicolon would divide the whole sentence and it would be shorten; a colon would work but after requested, when there is already a comma.

C. Question mark or Exclamation Point Outside Rule: would not work, becase it is an very polite and affirmative sentence.

D: A comma or period inside rule: actually, just a comma would work. Please, Cooper’s dad requested, go… Cooper’s dad requested must be in between commas as it is a vocative.

Hope this helps

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## A car initially moving at 9 m/s begins accelerating at its maximum acceleration of 4 m/s2. if the car maintains this acceleration, how much time will it take to cover 200 m?

a) The time the police officer required to reach the motorist was 15 s.

b) The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) The total distance traveled by the officer was 225 m.

Explanation:

The equations for the position and velocity of an object moving in a straight line are as follows:

x = x0 + v0 · t + 1/2 · a · t²

v = v0 + a · t

Where:

x = position at time t

x0 = initial position

v0 = initial velocity

t = time

a = acceleration

v = velocity at time t

a)When the officer reaches the motorist, the position of the motorist is the same as the position of the officer:

x motorist = x officer

Using the equation for the position:

x motirist = x0 + v · t (since a = 0).

x officer = x0 + v0 · t + 1/2 · a · t²

Let´s place our frame of reference at the point where the officer starts following the motorist so that x0 = 0 for both:

x motorist = x officer

x0 + v · t = x0 + v0 · t + 1/2 · a · t²      (the officer starts form rest, then, v0 = 0)

v · t = 1/2 · a · t²

Solving for t:

2 v/a = t

t = 2 · 15.0 m/s/ 2.00 m/s² = 15 s

The time the police officer required to reach the motorist was 15 s.

b) Now, we can calculate the speed of the officer using the time calculated in a) and the  equation for velocity:

v = v0 + a · t

v = 0 m/s + 2.00 m/s² · 15 s

v = 30 m/s

The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) Using the equation for the position, we can find the traveled distance in 15 s:

x = x0 + v0 · t + 1/2 · a · t²

x = 1/2 · 2.00 m/s² · (15s)² = 225 m

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## Which of the following statements about urban growth is true? a. The rate of urban growth in the world is decreasing. b. Urban sprawl is less environmentally damaging than upward growth. c. Upward growth is less environmentally damaging than urban sprawl. d. More people are moving away from cities than in previous years.

The integumentary system covers the surface of the body is true about the integumentry system.

Explanation:

The integumentary system includes the skin, nails, glands, hairs, and nerves. Its main role is to act as a barrier to protect the body from the outside environment. It also retains body fluids, regulates body temperature, eliminates waste products, and protects against disease.

The integumentary system is the largest organ in the body that covers the surface of the body.

Thus, The integumentary system covers the surface of the body is the true statement about the integumentry system.

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## The graph indicates Linda’s walk. Which best describes the graph? Linda started out moving, and then stopped moving after 6 seconds. Linda started moving away from the start point, and then moved closer. Linda never moved the entire trip. Linda’s path results in a negative slope.

a) The time the police officer required to reach the motorist was 15 s.

b) The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) The total distance traveled by the officer was 225 m.

Explanation:

The equations for the position and velocity of an object moving in a straight line are as follows:

x = x0 + v0 · t + 1/2 · a · t²

v = v0 + a · t

Where:

x = position at time t

x0 = initial position

v0 = initial velocity

t = time

a = acceleration

v = velocity at time t

a)When the officer reaches the motorist, the position of the motorist is the same as the position of the officer:

x motorist = x officer

Using the equation for the position:

x motirist = x0 + v · t (since a = 0).

x officer = x0 + v0 · t + 1/2 · a · t²

Let´s place our frame of reference at the point where the officer starts following the motorist so that x0 = 0 for both:

x motorist = x officer

x0 + v · t = x0 + v0 · t + 1/2 · a · t²      (the officer starts form rest, then, v0 = 0)

v · t = 1/2 · a · t²

Solving for t:

2 v/a = t

t = 2 · 15.0 m/s/ 2.00 m/s² = 15 s

The time the police officer required to reach the motorist was 15 s.

b) Now, we can calculate the speed of the officer using the time calculated in a) and the  equation for velocity:

v = v0 + a · t

v = 0 m/s + 2.00 m/s² · 15 s

v = 30 m/s

The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) Using the equation for the position, we can find the traveled distance in 15 s:

x = x0 + v0 · t + 1/2 · a · t²

x = 1/2 · 2.00 m/s² · (15s)² = 225 m

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## The graph shows the distance y, in miles, of a moving train from a station over a certain period of time, x, in hours: A graph titled Distance Vs Time is shown with Time in hours labeled on x-axis and Distance from Station in miles labeled on y-axis. The scale on the x-axis shows the numbers 1, 2, 3, 4, 5, 6, 7, and the scale on the y-axis shows the numbers 0, 40, 80, 120, 160, 200, 240, 280, 320. The graph shows a straight line joining the ordered pairs 0, 80, and 1, 120, and 2, 160, and 3, 200, and 4, 240. What is the speed (in miles per hour) of the train and why? 80 miles per hour, because speed is the initial value of the function 120 miles per hour, because speed is the distance traveled in unit time 240 miles per hour, because speed is the distance traveled in a certain time 40 miles per hour, because speed is the rate of change of distance

127=7 (mod n) means when 127 is divided by n, the division leaves a remainder of 7.

The statement is equivalent to
120=0 (mod n), meaning that n divides 120.

All divisors of 120 will satisfy the statement because 120 divided by a divisor (factor) will leave a remainder of 0.

Factors of 120 are:
n={1,2,3,4,5,6,8,10,12,15,20,24,30,40,60,120}, |n|=16.
You can count how many such values of n there are, and try to check that each one satisfies 127=7 mod n.

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## An object moving at 31m/s takes 6s to come to a stop. What is the object’s acceleration?

a) The time the police officer required to reach the motorist was 15 s.

b) The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) The total distance traveled by the officer was 225 m.

Explanation:

The equations for the position and velocity of an object moving in a straight line are as follows:

x = x0 + v0 · t + 1/2 · a · t²

v = v0 + a · t

Where:

x = position at time t

x0 = initial position

v0 = initial velocity

t = time

a = acceleration

v = velocity at time t

a)When the officer reaches the motorist, the position of the motorist is the same as the position of the officer:

x motorist = x officer

Using the equation for the position:

x motirist = x0 + v · t (since a = 0).

x officer = x0 + v0 · t + 1/2 · a · t²

Let´s place our frame of reference at the point where the officer starts following the motorist so that x0 = 0 for both:

x motorist = x officer

x0 + v · t = x0 + v0 · t + 1/2 · a · t²      (the officer starts form rest, then, v0 = 0)

v · t = 1/2 · a · t²

Solving for t:

2 v/a = t

t = 2 · 15.0 m/s/ 2.00 m/s² = 15 s

The time the police officer required to reach the motorist was 15 s.

b) Now, we can calculate the speed of the officer using the time calculated in a) and the  equation for velocity:

v = v0 + a · t

v = 0 m/s + 2.00 m/s² · 15 s

v = 30 m/s

The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) Using the equation for the position, we can find the traveled distance in 15 s:

x = x0 + v0 · t + 1/2 · a · t²

x = 1/2 · 2.00 m/s² · (15s)² = 225 m

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## What prevented the donner party from moving ahead to fort laramie as planned

The answer to the question: What would have bappened if Odysseus had not arrived in disguise, is, that he would have lost the element of surprise that he had been told by the goddess Athena he needed, in order to eliminate all the suitors that are after his wife Penelope´s hand, and he would have most probably been killed by them instead.

Explanation:

“The Odyssey” by Homer, is the epic poem that narrates the events that Odysseus must face in his return home from the Trojan War, and when he finally reaches Ithaca, where he is king. In book 17, Odysseus finally reaches Ithaca, and has been told previously that he must get rid of all of Penelope´s suitors. In order to do this, Athena helps him disguise him as an old beggar in order to preserve the element of surprise and protect him from the greed of the 20 suitors after Penelope. In this way, Odysseus learns first hand what is happening in his home and is able to come up with an appropriate plan to carry out what has been given to him by the gods.

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## A car moving at 10 m/s crashes into a tree and stops in 0.26 s. calculate the force the seat belt exerts on a passenger in the car to bring him to a halt. the mass of the passenger is 70 kg

The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies.

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface.

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h.

So the time for the pencil and eraser to touch is T=1.3449 hours.

Also time T can be expressed like T= 1h and 20 mins and 41.64 s