A body of mass 10 kg at rest is applied with perpendicular force of 4 N and 3 N at the same time, then at the end of 10 seconds its kinetic energy = .........

Options

A. 25j
B. 250 j
C. 125 j
D. 400 j

Answer

C

Explanation

Resultant force `F= [(4)^(2) + (3)^(2) ]^(1/2) =5`
`a=(5)/(m ) = (5)/(10) = 0 .5 m//s^(2)`
`v=v_(0) at`
`v=0 + 0.5 xx 10`
`v= 5m//s`
`k=(1)/(2) mv^(2)`
`=(1)/(2) xx 10 xx (5)^(2)`
`=5 xx 25 `
`=125 J`