A person prevents a 7,500N car with its brakes released from moving on a hill by pushing the car uphill with a force of 25,000N for 2 seconds. How much work is done?

The bar of prob. 5/82 is repeated here. the ends of the 0.4-m bar remain in contact with their re- spective support surfaces. end b has a velocity of 0.5 m/s and an acceleration of 0.3 m/s2 in the di- rections shown. determine the angular accelera- tion of the bar and the acceleration of end a.