Question

A window is 50 cm long. a stone is falling from a height of 40 cm above the window . It crosses the window in ? (Find the time )

Answer 1

We can use the kinematic equation
s= ut+1/2at²
Here s=40cm and 50cm
u(initial velocity)=0
a(acceleration due to gravity)=9.8
t is the time taken


s=0.4m
s=ut+1/2at^2
0.4=0xt + 1/2 x 9.8 x t^2
0.4=4.9t^2 t= √0.4/4.9
t= 0.285 s

s=0.5
s=it+1/2at²
0.5= (0 x t) + 1/2 x 9.8 x t^2
t^2=0.5/4.9 t^2= 0.1020
t=0.1010 seconds
Time taken to cover the window is 0.1010 sec
Total time taken=time taken to cover 40cm+time taken to cover 50cm=0.285+0.1010=0.386sec
Hope it helps!!
Plz mark it as the brainliest