A body of mass 10kg at rest is acted upon simultaneously by two forces 4 N and 3 N at right angles to each other. The kinetic energy of the body at the end of 10 sec is

Options

A. 100 J
B. 300 J
C. 50 J
D. 125 J

Answer

D

Explanation

Net force on body `= sqrt(4^(2)+3^(2))=5N`
`therefore a=F//m = 5//10=1//2 m//s^(2)`
Kinetic energy `= (1)/(2)mv^(2)=(1)/(2)m(at)^(2)=125 J`