Question

A ball is thrown upward with a speed of 20m/s. Fond the time take taken to reach the its top position. In this question if i use v= u +at the answer comes out to be 2sec, but if i use v^2-u^2=2as then the height comes out to be 20m and time comes out to be 1sec. I m very confused in this​

Answer 1

Answer:

the ball will travel for 2 seconds and complete a distance of 20 metres upwards

Step-by-step explanation:

These questions can be answered by making use of Newton's equations of motion. There are 3 equations of motions.

Using First Equation

v=u+at  

0=20−10t  

10t=20  

t=2

Using the Second equation,

v2=u2+2as  

02=202+2×(−10)×s  

20s=400  

s=20

Hence, the ball will travel for 2sec and will complete a distance of 20m

Hope this is helpful.....