Question

A body of mass 7.5 kg is moving with a velocity of 12.5 ms-1.
____ force is required to stop it in 3 sec.​

Answer 1

Answer:

-31.25 N (approx.)

Explanation:

we know that force = M×A

SO , given M = 7.5kg

U= 12.5 m/s

V = 0 ( as it stops in the end )

T= 3 sec

now acceleration ( A) = (V-U)/T

SO ( 0- 12.5) / 3

= -4.166 m/s^2 ( retarding ). (approx.)

so , M×A = 7.5 × ( -4.166)

= - 31.25 N ( approx.)

so , -31.25 N (approx.) of opposing force will be required to stop the car