A body of mass 2kg is travelling in a straight line along the x-axis. It collides with a second body of mass 3kg which is moving at -2m/s. The two bodies move off together at 3m/s. What is the initial velocity of the first body?

2u-32=53=15, 2u=15+6. Therefore, u=10.5m/s. This is a standard type of question, it is simply about conservation of momentum. Momentum (p) is equal to massvelocity. Initially, the first body has momentum 2u kgm/s as its mass is 2kg and its velocity is u. The second body has momentum -6 kgm/s. After the collision, the two bodies move off together at the same speed so the final momentum is 15 kgm/s. We can then rearrange to find u.

Answered by Caroline L. Physics tutor

2591 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

A pellet of mass 8.8 g embeds itself in a wooden block of 450 g which is suspended by a light in-extensible string. After the collision the block reaches a max height of 0.63 m. Calculate the initial velocity of the pellet.


what is the scape velocity?


A block of mass m is released from rest on a surface inclined at 30⁰ to the horizontal with a coefficient of friction of 0.3. How long does it take for the block to slide 1 m?


What is electromotive force (emf) and how can the emf of a battery be measured?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences