# physics

posted by .

A freight train has a mass of 2.1 × 10^7 kg. If the locomotive can exert a constant pull of 6.2 × 10^5 N, how long would it take to increase the speed of the train from rest to 77.7 km/h? (Disregard friction.)

• physics -

F=ma
solve for a (a=F/mass)

Vf=at conver km/hr to ms/s, solve for t.

## Similar Questions

1. ### physics

A freight train has a mass of 5 x 107 kg. If the locomotive can exert a constant pull of 12 x 105 N, how long would it take to increase the speed of the train from rest to 85 km/h
2. ### physics

A freight train has a mass of 6.5 107 kg. If the locomotive can exert a constant pull of 11.5 105 N, how long would it take to increase the speed of the train from rest to 85 km/h?
3. ### physics

A freight train has a mass of 3.2 × 107 kg. If the locomotive can exert a constant pull of 7.1 × 105 N, how long would it take to increase the speed of the train from rest to 74.6 km/h?
4. ### Physics

A freight train has a mass of 1.0 10^7 kg. If the locomotive can exert a constant pull of 7.5 10^5 N, how long does it take to increase the speed of the train from rest to 66 km/h?
5. ### Physics

A freight train has a mass of 1.7 107 kg. If the locomotive can exert a constant pull of 7.6 105 N, how long does it take to increase the speed of the train from rest to 64 km/h?
6. ### physics

A freight train has a mass of 1.6 × 10 7 kg. If the locomotive can exert a constant pull of 8.0 × 10 5 N, how long would it take to increase the speed of the train from rest to 80.3 km/h?
7. ### physics

A freight train has a mass of 3.1 × 107 kg. If the locomotive can exert a constant pull of 4.9 × 105 N, how long would it take to increase the speed of the train from rest to 71.9 km/h?
8. ### Physics

A freight train has a mass of 1.7 × 10^7 kg. If the locomotive can exert a constant pull of 5.2 × 10^5 N, how long would it take to increase the speed of the train from rest to 74.6 km/h?
9. ### physics

A freight train has a mass of 1.5 x 10^7 kg . If the locomotive can exert a constant pull of 7.5 X 10^5 N, how long does it take to increase the speed of the train from rest to 80 km /h?
10. ### Physics

A freight train has a mass of 1.2 107 kg. If the locomotive can exert a constant pull of 8.4 105 N, how long does it take to increase the speed of the train from rest to 88 km/h?

More Similar Questions