Question

an object is thrown vertically up with an initial velocity of 20m/s from the ground. find the maximum height will attain and time will it take to reach at the highest point. what is the work done by the force of gravity on the object on reaching the ground? take g=10m/s2​

Answer 1

Explanation:

Given:

u= 20m/s

v= 0m/s

g= -10m/s²

To calculate: height, work done by force of gravity.

Solution:

We know that,

v²=u²+2gh

but the body is falling so g will be negative.

thus, v²=u²-2gh

0=400-2×10×h

20h=400

(a) h=20m

(b) Work=F×s

Work= 10×20

Work=200N