Question

I need help with this problem.
A car starts from rest and travels for 5.0s with a constant acceleration of -1.5 m/s². What is the final velocity of the car? (Hint: Vi = 0 m/s)

Answer 1

Answer:7.5ms^-1

Explanation:

a = acceleration = 1.5 t = time = 5 sec Vi = initial velocity = 0 m/s Vf = final velocity using the equation Vf = Vi + at Vf = 0 + 1.5 x 5 = 7.5

Answer 2

Answer:

-7.5 m/s

Explanation:

$a = \dfrac{v_f - v_i}{t}$

Here given: a = -1.5 m/s², v = ?, vᵢ = 0, t = 5 s

Putting into formula:

$\rightarrow -1.5 = \dfrac{v_f - 0}{5}$

$\rightarrow v_f = -1.5(5)$

$\rightarrow v_f = -7.5$

Hence, the final velocity is -7.5 m/s.