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A more realistic car would cause the wheels to spin in a manner that would result in the ground pushing it forward with a constant force (in contrast to the constant power in Part A). If such a sports car went from zero to 31.0 mph in time 1.50 s , how long would it take to go from zero to 62.0 mph

User Jomofrodo
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1 Answer

6 votes

Answer:

3 seconds

Step-by-step explanation:

To solve this problem, we have to find the acceleration of the car.

Acceleration is given as:

a = (v - u) / t

Where v = final velocity

u = initial velocity

t = time taken.

From the question,

u = 0 m/s

v = 31 mph = 13.86 m/s

t = 1.5 seconds

Acceleration, a, will be:

a (13.86 - 0) / 1.5

a = 13.86 / 1.5

a = 9.24 m/s²

We are told that this kind of car operates with constant force. This means it operates with constant acceleration (since force and acceleration are directly proportional)

Therefore, when the final velocity of the car is 62 mph (27.72 m/s), time taken is:

a = (v - u) / t

=> t = (v - u) / a

t = (27.72 - 0) / 9.24

t = 3 seconds

It will take the car 5 seconds to go from zero to 62 mph.

User Fotanus
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