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## An object’s speed is the distance it travels _____ the amount of time it takes.

An object’s speed is the distance it travels _____ the amount of time it takes.

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## Greg is in a bike race. at mile marker four (out of ten), his speed was measured at 13.5mph. which best describes the measured number

Greg is in a bike race. at mile marker four (out of ten), his speed was measured at 13.5mph. which best describes the measured number

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## True or False: Florida law prohibits you from increasing your speed until the vehicle that is passing you has completed the passing maneuver.

True or False: Florida law prohibits you from increasing your speed until the vehicle that is passing you has completed the passing maneuver.

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## Regularly Tuning up a computer can assist keeping it running at Peak speed. True or False?

Regularly Tuning up a computer can assist keeping it running at Peak speed. True or False?

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## John goes for a run. From his house, he jogs north for exactly 5.0 min at an average speed of 8.0 km/h. He continues north at a speed of 12.0 km/h for the next 30.0 min. He then turns around and jogs south at a speed of 15.0 km/h for 15.0 min. Then he jogs south for another 20.0 min at 8.0 km/h. He walks the rest of the way home. Which is the correct plot of total distance as a function of time for John’s jog?

John goes for a run. From his house, he jogs north for exactly 5.0 min at an average speed of 8.0 km/h. He continues north at a speed of 12.0 km/h for the next 30.0 min. He then turns around and jogs south at a speed of 15.0 km/h for 15.0 min. Then he jogs south for another 20.0 min at 8.0 km/h. He walks the rest of the way home. Which is the correct plot of total distance as a function of time for John’s jog?

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## An airplane traveling 245 m/s east experiences turbulence, so the pilot slows down to 230 m/s. It takes the pilot 7 seconds to slow down to this speed. What is the acceleration of the plane? Round your answer to the nearest hundredth.

– 2.14 m/s^2

Explanation:

initial velocity , u = 245 m/s

final velocity, v = 230 m/s

time taken , t = 7 second

By use of first equation of motion,

v = u + a t

where, a be the acceleration.

Substitute the values of v, u and t

230 = 245 + a x 7

a = – 2.14 m/s^2

the acceleration is negative, it means the airplane is slowing.

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## How long will it take Karen to drive 975 miles, if her average speed is 65 miles per hour? how to write a formula

How long will it take Karen to drive 975 miles, if her average speed is 65 miles per hour? how to write a formula

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## [99 Points!!] Can someone help me with the following questions? (02.06 MC)Doug wants to get better at volleyball. In order to do this, he has created a list of skills he will need to improve. Which skill should get the most of his attention in order for him to excel at volleyball? Coordination Speed Power Balance (02.07 HC)Which of the following foods is rich in nutrients that will help hair, skin, and nails to grow? Lettuce Yogurt Carrots Apples (01.06 MC)The chart below shows four friends’ target heart rate zones. During their last spin class, each person averaged 170 beats per minute. Based on this information, who worked at the highest intensity level? Name Target Heart Rate Zone Janna 146bpm—188bpm Shania 145bpm—188bpm Paige 140bpm—182bpm Mimi 140bpm—185bpm A.Janna B Shania C Paige DMimi (02.06 MC)Emma has evaluated her skills and determined that she has many strengths, but power is her least-developed skill. She is signing up for a sport, but she wants to avoid anything that plays to her weakness. Which two sports should she avoid? Gymnastics and soccer Archery and bicycling Swimming and baseball Tennis and volleyball

Gymnastics and soccer since those sports are very active and involve a lot of physical cardio, soccer involves a lot of running.

Swimming and baseball are also some hard sports especially swimming since most are your muscles are used during that activity.

Hope this helps 😉

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## You may receive a ticket for driving at the posted speed limit a. never b. if the posted speed is not safe at the time c. only if you are driving a special vehicle like a truck

You may be driving at the posted speed limit and still receive a ticket if the posted speed  at that particular time when you’re driving.

It mostly occurs in  : heavy rain or snowstorm, a  hail, a hurricane or other natural disaster.

In such cases, it is advisable to reduce your speed and drive under ( or well under ) the posted or recommended speed. It is done as a measure to avoid accidents and unnecessary deaths.

Some other examples when you might receive a ticket for driving at the posted speed limit  include:  not slowing or accelerating for a passing ambulance or police vehicle and disobeying oral instructions given to you by traffic wardens.

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## A projectile is able to orbit the Earth at what speed?

A projectile is able to orbit the Earth at what speed?

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## Sasha sits on a horse on a carousel 3.5 m from the center of the circle. She makes a revolution once every 8.2 seconds. What is Sasha’s tangential speed?

Sasha sits on a horse on a carousel 3.5 m from the center of the circle. She makes a revolution once every 8.2 seconds. What is Sasha’s tangential speed?

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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: Categories

## A ship traveled for 4 hours heading west and for 5 hours heading north. If the total distance traveled was 119 miles, and the ship traveled 5 miles per hour faster west, at what speed was the ship traveling west

To answer this problem, we will use the formula of
hypotenuse:

c^2 = a^2 + b^2

Where,

c = total distance traveled / displacement = 119 miles

a = distance traveled north = 5 hours * x mph =  5 x

b = distance traveled west = 4 hours * (x + 5) mph = 4 (x
+ 5)

Substituting to the equation:

119^2 = (5 x)^2 + [4(x + 5)]^2

14,161 = 25 x^2 + 16 (x + 5)^2

14,161 = 25 x^2 + 16 (x^2 + 10 x + 25)

14,161 = 25 x^2 + 16 x^2 + 160 x + 400

0 = 41 x^2 + 160 x – 13,761

x =[ – b ± sqrt (b^2 – 4ac)]/ 2a

x = [- 160 ± sqrt (160^2 – 4 * 41 * (– 13,761))] / 2 * 41

x = – 1.95 ± 18.42

x = -20.37 , 16.47

Since speed cannot be negative, therefore x = 16.47

Therefore the speed of the ship travelling west is:

x +

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## Calculate the speed with which the moon orbits the earth given the distance from earth to moon as R = 3.84 · 108 m. (Astronomers note that the true orbital period of the moon, is 27.3 Earth days. Interestingly, this would mean that there are approximately 13 months in a year. Use the 27.3 days/month for T – the time required for one revolution in your calculation.)

This sounds pretty easy, in fact. The orbital motion can be assumed to be circular and with constant speed. Then, the period is the time to do one revolution. The distance is the length of a revolution. That is 2*pi*R, where R is the distance between the Moon and the Earth (the respective centers to be precise). In summary, it’s like a simple motion with constant speed:

v = 2*pi*R/T,

you have R in m and T is days, which multiplied by 86,400 s/day gives T in seconds.

Then v = 2*pi*3.84*10^8/(27.3*86,400) = 1,022.9 m/s ~ 1 km/s (about 3 times the speed of sound 🙂

For the Earth around the Sun, it would be v = 2*pi*149.5*10^9/(365*86,400)~ 29.8 km/s!

I know it’s not in the problem, but it’s interesting to know how fast the Earth moves around the Sun! And yet we do not feel it (that’s one of the reasons some ancient people thought crazy the Earth not being at the center, there would be such strong winds!)

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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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## A machine that provides both constant speed and maximum resistance throughout the full range of motion provides what type of muscular contraction?

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 second harmonic of a guitar string has a frequency of 120 hz. what is the length of the guitar string if the speed of the waves on the string is 110 m/s?

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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## You drop a stone down a well that is 9.5 m deep. how long is it before you hear the splash? the 9) speed of sound in air is 343 m/s and air resistance is negligible.

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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## A man standing 9 feet from the base of a lamppost casts a shadow 6 feet long. if the man is 6 feet tall and walks away from the lamppost at a speed of 30 feet per minute, at what rate, in feet per minute, will his shadow lengthen?

A man standing 9 feet from the base of a lamppost casts a shadow 6 feet long. if the man is 6 feet tall and walks away from the lamppost at a speed of 30 feet per minute, at what rate, in feet per minute, will his shadow lengthen?

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## Which statement best describes how a catalyst can speed up a chemical reaction? The catalyst makes lower energy pathways available. The catalyst increases the concentration of products. The catalyst binds to enzymes to release substrates. The catalyst increases the concentration of reactants.

There are two systems in the human body that are responsible for the coordination between the functions of different systems to achieve the unity of the living organism’s body. These two systems are the nervous system and the endocrine system. The action of the nervous system is fast and takes a short time, while the action of the endocrine system is slow and takes a long time.

The functional unit of the nervous system is the nerve cell or the neuron. The neuron consists of a cell body and the axon. The cell body starts with the dendrites that receive the messages or the impulses from other neurons or from different sense organs or receptors. These impulses are then transmitted through the cell body. The cell body contains a nucleus and different organelles which help the nerve cell to perform its functions. The nerve impulse is then transmitted to the axon.

The axon is an extension from the cell body. There are some cells called Schwan cells that secrete a myelin sheath to insulate the axon from the surrounding medium. The insulated axons have more ability to conduct the impulses than non-insulated axons. The axon ends with the terminal arborizations. The terminal arborizations of a nerve cell connect to the dendrites of the next cell or to the afferent organ. The gaps between the dendrites and the terminal arborizations are called the synapses.

The nerve impulse is an electrochemical phenomenon i.e. an electrical phenomenon with a chemical nature. The membrane of the axon acts as a barrier between an outside positively charged medium and an inside negatively charged medium. This makes a potential difference of  -70mV. This state is called the resting potential. When the membrane is subjected to a stimulus, the positive charges enter to inside and the negative charges exit to the outside. The potential difference now becomes +40mV. This state is called the depolarization state. The point of stimulation acts as a new stimulus for the next point and so on. The membrane sooner gains its permeability again and the positive charges return to the outside and the negative charges to inside. This state is called repolarization.

The nerve impulse reaches the synapse. There are some neurotransmitters that are excited by the nerve impulse coming and carry the message across the membrane. Some receptors receive theses neurotransmitters on the dendrites of the next neuron. These receptors act as a stimulus for the new cell.

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## The speed of a tidal wave in meters/second is given by the square root of the product of the acceleration due to gravity on Earth (9.8 meters/second^2) and the depth of the ocean in meters. If the ocean is 500 meters deep, the speed of the tidal wave will be m/s.

The basis to respond this question are:

1) Perpedicular lines form a 90° angle between them.

2) The product of the slopes of two any perpendicular lines is – 1.

So, from that basic knowledge you can analyze each option:

a.Lines s and t have slopes that are opposite reciprocals.

TRUE. Tha comes the number 2 basic condition for the perpendicular lines.

slope_1 * slope_2 = – 1 => slope_1 = – 1 / slope_2, which is what opposite reciprocals means.

b.Lines s and t have the same slope.

FALSE. We have already stated the the slopes are opposite reciprocals.

c.The product of the slopes of s and t is equal to -1

TRUE: that is one of the basic statements that you need to know and handle.

d.The lines have the same steepness.

FALSE: the slope is a measure of steepness, so they have different steepness.

e.The lines have different y intercepts.

FALSE: the y intercepts may be equal or different. For example y = x + 2 and y = -x + 2 are perpendicular and both have the same y intercept, 2.

f.The lines never intersect.

FALSE: perpendicular lines always intersept (in a 90° angle).

g.The intersection of s and t forms right angle.

TRUE: right angle = 90°.

h.If the slope of s is 6, the slope of t is -6

FALSE. – 6 is not the opposite reciprocal of 6. The opposite reciprocal of 6 is – 1/6.

So, the right choices are a, c and g.

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## If the rate-determining step limits the speed of a reaction, which statement is correct? Even if one or more fast steps occur in a reaction, the overall reaction cannot proceed any faster than the slowest step. If the first step is slow and the second step is fast, then the second step should determine the rate of the overall reaction. Increasing the concentration of a molecule that occurs in a fast step after a slow step will increase the overall rate of the reaction. In a unimolecular reaction where A decomposes to B and C, the rate of the reaction will decrease if the concentration of A is increased.

A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.

Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).

For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.

Activation energy of reverse and forward reactions is related by:

Activation energy of reverse rxn = Activation energy of forward rxn – ΔH rxn

=> Activiation energy of reverse rxn = 102 kJ/mol – 55 kJ/mol = 47 kJ/mol

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## LAW ENFORCEMENT: A police accident investigator can use the formula S=25L‾‾‾√S=25L to estimate the speed s of a car in miles per hour based on the length l in feet of the skid marks it left. How fast was a car traveling that left skid marks 109 feet long?

Option C – BD=76 cm

Step-by-step explanation:

Given : You are designing a diamond-shaped kite. you know that AD = 44.8 cm, DC = 72 cm, and AC = 84.8 cm.

To find : How long BD should it be?

Solution :

First we draw a rough diagram.

The given sides were AD = 44.8 cm, DC = 72 cm and AC = 84.8 cm.

According to properties of kite

Two disjoint pairs of consecutive sides are congruent.

DC=BC=72 cm

The diagonals are perpendicular.

So, AC ⊥ BD

Let O be the point where diagonal intersect let let the partition be x and y.

AC= AO+OC

AC= …….

Perpendicular bisect the diagonal BD into equal parts let it be z.

BD=BO+OD

BD=z+z

Applying Pythagorean theorem in ΔAOD

where H=AD=44.8 ,P= AO=x , B=OD=z  ………

Applying Pythagorean theorem in ΔCOD

where H=DC=72 ,P= OC=y , B=OD=z  …………

Subtract  and    ……….

Add equation  and , to get values of x and y   Substitute x in   Substitute value of x in equation , to get z     We know, BD=z+z

BD= 38.06+38.06

BD= 76.12

Nearest to whole number BD=76 cm

Therefore, Option c – BD=76 cm is correct.

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## The speed of sound at 0°C is 331.5 m/s. Calculate the speed of sound in the room at 20.0°C.

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