Question

Find the initial velocity of a car which stops in 10sec, after applying brakes at the rate of 2m/s²

Answer 1

`20\ m/s`

Step-by-step explanation:

Since we are given time, acceleration, and final velocity, we can use the following formula to find the initial velocity:

`v_f = v_i + at`

Our given values:

`v_f = 0\\a = -2\\t = 10\\`

Acceleration is negative because the car is slowing down.

Add the values to the formula, and solve for
`v_i`:

`v_f = v_i + at\\0 = v_i + (-2)(10)\\0 = v_i -20\\20 = v_i`