Question

An object of mass `100kg` is accelerated uniformly from a velocity of `5m//s` to `8m//s` in `6 s`. Calculate the initial and final momentum of the object. Also, find the magnitude of the force exerted on the object.

Answer 1

Correct Answer - 500 kg m `s^(-1)` ; 800 kg m `s^(-1)`; 50 N
Initial velocity of the object, u = 5 m/s
Final velocity of the object, v = 8 m/s
Mass of the object, m = 100 kg
Time take by the object to accelerate, t = 6 s
Initial momentum `= mu = 100 xx 5 = 500 kg ms^(-1) `
Final momentum `= mv= 100 xx 8 = 800 kg ms^(-1)`
Force exerted on the object,`F=(mv-"mu")//(t)`
`=m(v-u)//(t)`
`= (800-500)`
`=(300)//(6)`
=50 N
Initial momentum of the object is 500 kg `ms^(-1)`
Final momentum of the object is 800 kg `ms^(-1)`. Force exerted on the object is 50 N.