wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

A boy is standing on top of a tower of height 85m and throws a ball in the vertically upward direction with a certain speed. If 5.25 seconds later he hears the ball hitting the ground, then the speed with which the boy threw the ball is (take g = 10 m/s2 , speed of sound in air = 340 m/s)

A
6 m/s
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
8 m/s
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
10 m/s
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
12 m/s
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B 8 m/s
Time taken by sound =85340=0.25sec
Time taken by the ball = 5.25 – 0.25 = 5 sec.
Now
85=u×512×10×25
U = 8 m/sec

flag
Suggest Corrections
thumbs-up
1
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Applying SHM
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon