How much force is required to produce an acceleration of 2 m s 2 in an object of mass 0 . 8 kg ?

Given, Mass m = 0 . 8 kg ; Acceleration a = 2 m s 2 . According to Newton's second law of motion, Force, F = m a F = 0 . 8 × 2 F = 1 . 6 N

A cricket ball of mass 100 g moving with a speed of 30 m s is brought to rest by a player in 0 . 03 s. Find the average force.

Given: Mass m = 100 g = 0 . 1 kg Initial speed u = 30 m s Final speed v = 0 Time t = 0 . 03 s a = v - u t a = 0 - 30 0 . 03 = - 1000 m s 2 From Newton's second law, Force F = m a F = ( 0 . 1 ) × ( - 1000 ) = - 100 N

An object of mass 20 kg moving with an acceleration of 2 m s 2 . Find the rate of change of momentum.

Given: Mass m = 20 kg ; Acceleration a = 2 m s 2 From Newton's second law, Force F = m a F = 20 × 2 = 40 N According to Newton's second law of motion: The rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of the force. Therefore, Rate of change of momentum = Force ∆ p ∆ t = F = 40 N

Which object will require more force? One object of 2 kg mass is moving with acceleration of 5 m s 2 . Another object has acceleration of 2 m s 2 and the weight is 4 kg .

For the first object: Mass, m 1 = 2 kg ; Acceleration, a 1 = 5 m s 2 Force, F 1 = m 1 a 1 = 2 × 5 = 10 N For the second object: Mass, m 2 = 4 kg ; Acceleration, a 2 = 2 m s 2 Force, F 2 = m 2 a 2 = 4 × 2 = 8 N Therefore F 1 > F 2 The first object will require more force.