Question

A stone is projected horizontally with velocity 20m/s from top of a tall building.Calculate it's position and velocity after 3 sec neglecting the air resistance.

Answer 1

Answer:

105m

Explanation:

u=20m/s

g=10m/s^2

t=3s

s=ut+1/2gt^2 at

or,s=20×3+1/2×10×3×3

or,s=105m

Answer 2

Answer

Given,

u = 20m/s

t=3sec

s=?

V=?

Now,

S=ut+1/2 at²

= 20x3+5t²

= 60+5x9

= 60+45

=105m Ans

Again,

v=s/t

= 105/3

=35m/s Ans