Question

calculate the power delivered by a force which acts on the body of mass 10kg and it acquired the velocity of 10m/sec under acceleration of 2m/sec2

Answer 1

power is rate of change of work and work is force* displacement

we are given with

m= 10kg

a= 2 m/s²

so F= m×a= 20 N

$v^{2} - u^{2}= 2ax\\x=( v^{2}-u^{2})/ 2a$

u=0 since it starts from rest and v= 10m/s²

so x=10²/(2×2)=  25 m

hence work  =  20 × 25 = 500 joule

t= v/a= 10/2 = 5 sec

hence power delivered = w/t = 500/ 5 = 100 Watt