There is a train A. On the roof of A is another frictionless train B of mass Mb. A mass Mc hangs off the front of A and is attached to the front of B by rope and frictionless pulley. How fast should A accelerate so that B wont fall off the roof of A.

You must carefully draw a diagram. The key to this question is to find from what perspective you should view it. The easiest way is to see that B wants to accelerate due to the weight of C. This is unaffected by the motion of A. We simply need to accelerate A at the same rate that B would accelerate so there will be no relative motion and so B wont fall off. We have the acceleration of b = (Mc*g)/(Mb+Mc) So that is what the acceleration of A should be.

Answered by Sean O. Physics tutor

1940 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

Electrons moving in a beam have the same de Broglie wavelength as protons in a separate beam moving at a speed of 2.8 × 10^4 m/s . What is the speed of the electrons?


If a vehicle A, 1000kg moving at 5m/s collides with vehicle B, 750kg, moving in the opposite direction at 8m/s assuming no rebound what is the velocity of the vehicles after collision.


How, given the threshold frequency and the kinectic enery of a photon, do you determine the frequency of the phton?


How can an object be accelerating if it does not change in speed?


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 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences