Question

The most massive of the shikansen are the series 200 trains, yet they are among the fastest. Series 200 trains can reach speeds of 275 km/h. If a 16-car series 200 trains has a maximum kinetic energy of 2.78 x 10^9 J, what is its mass?

Answer 1

Kinetic energy = 1/2 m (v^2)

you know the KE and the speed
(have to convert km/h into m/s)

find the "m" using the formula

Answer 2

5.93 X 10^5 kg