2 A car of mass 1800 kg is towing a trailer of mass 400 kg along a straight horizontal road. The car and trailer are connected by a light rigid tow-bar. The car is accelerating at \(1.5 \mathrm {~m} \mathrm {~s} ^ { - 2 }\). There are constant resistance forces of 250 N on the car and 100 N on the trailer.

1. Find the tension in the tow-bar.
2. Find the power of the engine of the car at the instant when the speed is \(20 \mathrm {~m} \mathrm {~s} ^ { - 1 }\).