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3 years ago

!!HELP HELP!!

Physics

1 answer:

borishaifa [10]3 years ago

6 0

Answer:

7.5s

Explanation:

Given parameters:

Velocity = 30m/s

Deceleration = 4m/s²

Unknown:

Time it takes for the car to come to complete rest = ?

Solution:

To solve this problem, we use the kinematics expression below:

v = u + at

Since this is a deceleration

v = u - at

v is the final velocity

u is the initial velocity

a is the acceleration

t is the time taken

v - u = -at

0 - 30 = -4 x t

-30 = -4t

t = 7.5s

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