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4 years ago

How to find time(t) when initial velocity(u),final velocity(v) is given and acceleration(a) is not constant ?

1 answer:

4 0

You can do this if you have a working knowledge of calculus.

You need to model the acceleration as a function of time, ie obtain a function a(t) that gives acceleration a for any time t.

Using the fundamental theorem of calculus, you should integrate a(t) from t=0 to a variable value of time t. This should get you an expression in terms of t.

Now set this expression equal to the difference of the final and initial velocity, v-u, and solve for t.

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you are driving along a country road when you suddenly notice a log in the road ahead of you and immediately apply your brakes.

DiKsa [7]

a. The car will not hit the tractor.

b. The car would travel a distance of 52.07 m before stopping

c. At the moment when the car stopped, the tractor is 11.5 m in front of the car.

Linear motion

From the question, we are to determine of you will hit the tractor before you stop

First, we will determine the time it will take the car to stop

From the given information,

Initial velocity, u = 27.0 m/s

a = -7 m/s² (Negative sign indicates deceleration)

v = 0 m/s (Since the car will come to stop)

From one of the equations of linear motion,

v = u + at

Where v is the final velocity

u is the initial velocity

a is the acceleration

and t is the time taken

Putting the parameters into the equation, we get

0 = 27 + (-7)t

7t = 27

t = 27/7

t = 3.857 secs

This is the time it will take the car to stop

Now, we will determine the distance the car would travel after applying the brakes

Using the formula

S = (u + v) / t

Where S is the distance traveled

S = [(27 + 0) / 2] * 3.857

S = 13.5 * 3.857

S = 52.0695 m

S ≅ 52.07 m

This means the car would travel 52.07 m after applying the brakes

Now, we will determine the distance the tractor would have traveled when the car came to a stop

Speed of the tractor = 10.0 m/s

Time taken for the car to stop = 3.857 secs

Using the formula,

Distance = Speed × Time

Distance = 10.0 × 3.857

Distance = 38.57 m

Now, we will determine the distance between the car and the tractor when the car finally stopped

Distance between the car and the tractor = Distance ahead + Distance traveled by the tractor after the car stopped - Distance traveled by car after applying the brakes

Distance between the car and the tractor = 25 m + 38.57 m - 52.07 m

Distance between the car and the tractor = 11.5 m

Therefore, the distance the tractor was ahead of the car + the distance the tractor traveled after the car stopped is more than the distance the car traveled after applying the brakes (25 m + 38.57 m > 52.07), the car will not hit the tractor.

To know more about distance, refer: brainly.com/question/10903482

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[NOTE: THIS IS AN INCOMPLETE QUESTION. THE COMPLETE QUESTION IS: You are driving your car along a country road at a speed of 27.0 m/s. as you come over the crest of a hill, you notice a farm tractor 25.0 m ahead of you on the road, moving in the same direction as you at a speed of 10.0 m/s. you immediately slam on your brakes and slow down with a constant acceleration of magnitude 7.00 m/s2 .

a.will you hit the tractor before you stop?

b.how far will you travel before you stop or collide with the tractor?

c.if you stop, how far is the tractor in front of you when you finally stop?]

7 0

1 year ago

How do I do this question?

iren2701 [21]

You take 10.0/12.0 and you will get your answer

3 0

3 years ago

Read 2 more answers

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