Two cars are moving at constant speeds in a straight line along a major highway. The first is travelling at 20ms^-1 and the second at 28m^-1. If the second car is 6km behind the first car, how much time will it need to catch up with the first car

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.