Two trains are heading in opposite directions on the same track. Train X has a mass of 16000kg and a speed of 2.8m/s. Train Y has a mass of 12000kg and a speed of 3.1m/s. At what speed do the joined trains move off together immediately after the collison?
Remembering that if the velocities are in different directions they have different signs:Total momentum before=Total momentum afterMomentum=mass x velocityTotal momentum before= (16000x2.8)+(12000x(-3.1))=7600kgm/sCombined mass =28000kgVelocity after collision =7600/28000 =0.27m/s (2dp)
CJ
Related Physics A Level answers
All answers ▸What is "half-life"?
A phone is knocked off a table 800cm of the ground. If the phone is 650g a) what is the gravational potential of the phone? b)what speed will the phone hit the floor at? c)How long will it take for the phone to hit the floor?
An infared wave has a wavelength of 1.5 x10^–6 m. The speed of this wave is 2.2 × 10^8 m/s. Calculate the frequency of the wave. Give your answer in standard form and to 2 significant figures.
You are asked to find the Young modulus for a metal using a sample of wire. *(a) Describe the apparatus you would use, the measurements you would take and explain how you would use them to determine the Young modulus for the metal.