Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • Solve it, A spherical ball of mass 20 kg is stationary at the top of a hill of height 100 m . It rolls down a smooth surface to the ground, then climbs up another hill of height 30 m and finally rolls down to a horizontal base at a height of 20 m above th

A spherical ball of mass 20 kg is stationary at the top of a hill of height 100 m . It rolls down a smooth surface to the ground, then climbs up another hill of height 30 m and finally rolls down to a horizontal base at a height of 20 m above the ground. The velocity attained by the ball is

Option 1)

10 m/s

 Option 2)

34 m/s
Option 3)

40 m/s

 Option 4)

20 m/s

Answers (1)

best_answer

As we learnt in

If only conservative forces act on a system, total mechnical energy remains constant -

K+U=E\left ( constant \right )

\Delta K+\Delta U=0

\Delta K=-\Delta U

-

 

 Since surface is smooth so the motion of ball is not rolling motion change in kinetic energy = loss in potential energy

\Rightarrow\ \frac{1}{2}mv^{2}=mg(h_{i}-h_{f})

    v=\sqrt{}{2g(h_{i}-h_{f})}=\sqrt{}{2\times 10\times 80}

    v = 40 m/s

Correct answer is 3


Option 1)

10 m/s

This is an incorrect option.

Option 2)

34 m/s

This is the correct option.

Option 3)

40 m/s

This is an incorrect option.

Option 4)

20 m/s

This is an incorrect option.

Posted by

perimeter

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

Trending Articles/News

anam-khan

JEE Mains 2025 session 1 registration deadline on November 22; apply on jeemain.nta.nic.in
anam-khan

BTech Admission 2025 Live: JEE Mains, SRMJEEE, MET registrations underway; MHT CET syllabus updates
anam-khan

Centre issues coaching guidelines, prohibits centres from using false claims like '100% selection'

Latest Question