Question

a body of mass is 2kg initially at rest is acted upon simultanwously by two forces one of 4 N and other of 3 N actung at right angles to each other. find the kinetic energy of body after 20 seconds.​

Answer 1

Explanation:

Since it is acted upon simultaneously by two forces 4N and 3N at right angles, net force =

$\sqrt{ {4}^{2} + {3}^{2} } = 5 \: newton$

F=ma

a = 5/2 = 2.5 m/s^2

Kinetic Energy K.E. =

$\frac{1}{2} m {v}^{2} = \frac{1}{2}m {(at)}^{2}$

K.E. = 1/2 × 2 × 2.5 × 20

K.E. = 50 J