Question

a body of mass 6kg moving forward on horizontal surface with an initial velocity of 8m/s comes to rest after 3s. if one wants to keep this body moving on the same surface with velocity of 8m/s, the force required is​

Answer 1

Answer:

16 N

Explanation:

v = 0 m/s

u = 8 m/s

m = 6 kg

t = 3s

substitute it in v + at = u

0 + 3a = 8

a = 2.6 m/s

substitute acceleration in f = ma

F = 6 * 2.6

16 N

Answer 2

Given: A body of mass 6 kg moving forward horizontal surface with an initial velocity of 8 m/s comes to rest after 3 seconds.

To find: Force required to keep the body moving on the same surface with velocity 8 m/s

Explanation: Initial velocity (u) = 8 m/s

Final velocity (v)= 0

Time = 3 seconds

Using kinematics formula,

a = v-u / t

= 0-8 / 3

= -8/3 m/s^2

The acceleration of the body is -8/3 m/s^2

For body to move at velocity of 8 m/s, the force has to be exerted in the opposite direction of the negative acceleration.

Therefore, acceleration should be 8/3 m/s^2

Mass of body = 6 kg

Force required= Mass * Acceleration

= 6 * (8/3)

= 16 N

Therefore, force required to keep the body moving on the same surface at 8 m/s is 16 N.