The velocity time graph for the veticaly component of the velocity of a body thrown upwards from the ground and landing on the roof of a building is given in the figure.The height of the building is:

Options

A. 50 m
B. 40 m
C. 20 m
D. 30 m

Answer

B

Explanation

Height = algebraic sum of area under `u - t` graph
` = (1)/(2) xx 30 xx 3 - (1)/(2) xx 10 xx 1`
`= 40 m`