Question

A body of mass 3 kg retarded
uniformly from 40 meter per second to 10 meter per second in 10 second
find the retarding force.​

Answer 1

mass of the body,m = 3kg

initial velocity,u =40 m/s

final velocity , v = 10 m/s

we know that, retarded force = Force

Force= Mass x Acceleration

here, Mass is given,not acceleration

to calculate Acceleration (a)

we can use equation of motion:

v= u + at

or v2 = u2 + 2 as

but we are

neither given the distance travelled (s) nor time (t)

so we can't calculate Acceleration.

therefore,retarded force can't be calculated.

Answer 2

Answer:

As the body is retarding ,the value of acceleration will be in negative.

since, force=mass×acceleration

therefore force can not be in negative

hope it helps