1) A car covers one-quarter of the distance to the next town at 40km/h, another quarter at 50 km/h and the rest at 90km/h. Find the car's average speed for the entire distance.
2) In order to qualify for the finals in a racing event, a race car must achieve an average speed of 250km/h on a track with a total length of 1600m. If a particular car covers the first half of the track at an average speed of 230 km/h, what minimum average speed must it have in the second half of the track in order to qualify?
3) Two cars travel in the same direction along a straight highway, one at a constant speed of 55mi/h and the other at 70mi/h. a) Assuming that they start at the same point, how much sooner does the faster car arrive at a destination 10 miles away? b) How far must the faster car travel before it has a 15-min lead on the slower car?
4) An object with an initial velocity 8m/s moves along a straight line with constant acceleration and travels 640m in 40s. For the 40-s interval, find a) the average velocity and b) the final velocity and c) the acceleration of the object.
5) Just as a car accelerates from rest with an acceleration of 1.4m/s2, a bus moving with a constant speed of 12m/s passes in a parallel lane in the same direction. a) How long does the car take to overtake the bus? b) How fast the car then be going? c) How far will the car then have traveled?
Step by step solutions provided.