A body of mass 5 kg has momentum of 10 kg ms^(-1) when a force of 0.2 N is applied on it for 10 seconds , what is the change in the kinetic energy ?

A body of mass 5 kg has momentum of 10 kg ms^(-1) when a force of 0.2

1.	A body of mass 5 kg has momentum of 10 kg ms^(-1) when a force of 0.2 N is applied on it for 10 seconds , what is the change in the kinetic energy ?
Answer» `1.1` J `2.2`J `3.3` J `4.4` J Solution :`v_(0) =p/m = 10/5 = 2 ms^(-1)` ACCELERATION `a = F/m = (0.2)/5 = 0.04 ms^(-2)` ` v = v_(0)+at` ` = 2+ 0.04 xx10` ` = 2+0.4` ` = 2.4 ms^(-1)` ` :. ` CHANGE in kinetic energy `DeltaK = 1/2 mv^(2) - 1/2 mv_(0)^(2)` ` = 1/2 m(v^(2) -v_(0)^(2))` `= 1/2 xx5(2.4^(2)-2^(2))` ` = 1/2 XX(5.76 -4.00)` `= 1/2 xx5xx1.76 ` = 4.4 J