Arailroad car with a mass of 30,000 kg is moving at 2.0 m/s when it runs into an at-rest freight car with an equal mass. the cara lock together. what is their final velocity?
a. 2.0 m/s
b. 0.5 m/s
c. 60,000 kg-m/s
d. 1.0 m/s

The starship enterprise is caught in a time warp and spock is forced to use the primitive techniques of the 20th century to determine the specific heat capacity of an unknown mineral. the 125-g sample was heated to 96.3°c and placed into a calorimeter containing 85.9 g of water at 20.0°c. the heat capacity of the calorimeter was 14.2 j/k. the final temperature in the calorimeter was 24.5°c. what is the specific heat capacity (in j/g°c) of the mineral? enter to 4 decimal places.