Question

a ball is thrown vertically upward from a building with a speed of 30 m/s .It reaches the ground in 8 s calculate the height of the building and g=10m/s

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Answer 1

Step-by-step explanation:

Initial velocity of the ball (u)=30m/s

Acceleration due to gravity (g)= -10m/s^2(as the ball is being thrown up)

Time taken to reach the ground=8s

Time to ascend=Time to descend

So, time taken by the ball to reach the max. height=8/2s=4s

Height of the building (s)=

ut+1/2gt^2

=30×4 + 1/2×(-10)×4×4

=40m

Hope you got it!