A certain force exerted for 1 . 2 seconds raises the speed of an object from 1 . 8 m s to 4 . 2 m s . Find the acceleration. If mass of the object was 5 . 5 kg . Calculate the force applied.

Given, mass of the body m = 5 . 5 kg Initial velocity u = 1 . 8 m s Final velocity v = 4 . 2 m s Time interval t = 1 . 2 s From newton's second law, the force exerted on the body is given by, F = m v - u t → 1 , Substituting the values in equation 1 we get, F = 5 . 5 ( 4 . 2 - 1 . 8 ) 1 . 2 ⇒ F = 11 N From Newton's second law F = ma , a = 11 5 . 5 ⇒ a = 2 m s 2

A certain force exerted for 1 . 2 seconds raises the speed of an object from 1 . 8 m s to 4 . 2 m s . Find the acceleration. If mass of the object was 5 . 5 kg . Calculate the force applied.

Given, mass of the body m = 5 . 5 kg Initial velocity u = 1 . 8 m s Final velocity v = 4 . 2 m s Time interval t = 1 . 2 s From newton's second law, the force exerted on the body is given by, F = m v - u t → 1 , Substituting the values in equation 1 we get, F = 5 . 5 ( 4 . 2 - 1 . 8 ) 1 . 2 ⇒ F = 11 N From Newton's second law F = ma , a = 11 5 . 5 ⇒ a = 2 m s 2

A force of 2 N acting on a body changes its velocity uniformly from 2 m s to 5 m s in 10 s . Calculate the mass of the body.

Given, initial velocity u = 2 m s Final velocity v = 5 m s Time interval t = 10 s Force acting on the body F = 2 N From newton's second law, force acting on the body is given by, F = m v - u t → 1 , substituting the values in equation 1 we get, 2 = m ( 5 - 2 ) 10 ⇒ m = 20 3 kg ⇒ m = 6 . 67 kg

A body of mass 10 kg moving with a velocity of 25 m s comes to rest in 10 s . Find the change in momentum.

Given, mass of the body m = 10 kg Initial velocity u = 25 m s Final velocity v = 0 m s Time interval t = 10 s Change in momentum is given by equation m ( v - u ) → 1 Substituting the above values in equation, we get 10 0 - 25 = - 250 kg m s