Question

a body of mass 4 kg is dropped from a height of 1 metre its kinetic energy as it touches the ground is(g=10m/s-2)
options
40N
40J
40kgf
40N/m square​

Answer 1

Answer:

Explanation:

(a)980,

(b)980J,  

(c)14m/s

(a). Mass of the Body = 10 kg.

Height = 10 m.

Acceleration due to gravity = 9.8 m/s².

Using the Formula,Potential Energy = mgh

= 10 × 9.8 × 10 = 980 J.

(b). Now, By the law of the conservation of the Energy, Total amount of the energy of the system remains constant.

∴ Kinetic Energy before the body reaches the ground is equal to the Potential Energy at the height of 10 m.

∴ Kinetic Energy = 980 J.