Question

a stone is thrown horizontally from the top of tower 78.4m high with a velocity 20m/s. when and where does the stone hit the ground? ​

Answer 1

Step-by-step explanation:

Answer

For I

st

stone u

h

=10 m/s

u

v

=0;s

v

=−78.4 m;g=−9.8 m/s

2

s

v

=u

v

t+

2

1

at

2

⇒−78.4=

2

−9.8

×t

2

t

2

=16 sec.⇒t=4 sec.

Distance travelled in horizontal direction in 4 s

s

n

=10×4=40 m

For II

nd

stone →u

h

=20 m/s;u

v

=0;s

v

=−78.4 m;g=−9.8 m/s

2

It will also take same time as the vertical distance travelled is same. Distance travelled in horizontal direction by II

nd

stone in 4 s

s

n

=20×48=80 m

total distance between stones =40+80=120 m

Answer 2

Answer:

Step-by-step explanation:

U=0

S=78.4m

S=ut+1/2at*t

t=4s

Horizontal displacement=20*4

=80m