Question

A motorcar is moving will a velocity of 108 km/h and it takes 4 s to stop after the brakes are applied . calculate the force exerted by the brakes on the motorcar if its mass along with the passengers is 1000 kg.
explain​

Answer 1

Explanation:

Force=mass*acceleration

f=m×

t

v−u

f=1000×

4

0−108×

18

5

=1000×(−7.5)

∴f=−7500N

opposing force is denoted by negative sign.

Answer 2

Answer:

Force = mass*acceleration

f = m ×  $\frac{v - u }{t}$

f = 1000 × $\frac{0-108\times \frac{5}{18} }{4}$

 = 1000 × (−7.5)

∴ f = −7500N

opposing force is denoted by negative sign.