Physics, asked by peetakatniss4ever, 1 year ago

pls tell me how to do this sum. it's urgent....tomorrow's my exam

Attachments:

Answers

Answered by Abir12

1.g=10m/s and took 20 sec to fall down therefore depth =(10*20)=200 m
2. speed of sound =330m/s,depth =200m
time for echo =(330/200)s=1.65 s

peetakatniss4ever: but the answer given is 26.1 i need a better workout for the sum

saka82411: Time taken by the ball to hot the water surface = 20 sec

Initial velocity = 0 , acceleration = g = 10m/s²

The height of well = H

s = ut + 1/2 a t²

H = 0 +1/2 * 10*20*20

H = 2000 meter

When pebble strikes the surface then sound is produced and it comes to observer by travelling the distance of the well.

Velocity of sound = 332 m/s , distance = H = 2000 m

time taken by sound to come to observer = t = distance/speed = 2000/332 = 6.02seconds.

The sound will be heard after 20 + 6.02 = 26.02 seconds.

saka82411: Hope this helps you!!!!

peetakatniss4ever: thanks

saka82411: you are welcome!!!

Answered by balu58

Answer:

eftvyb to know byvtcr be h

Previous Question

Next Question