Basic suvat stuff
a, b and c are 3 points lying in that order on a straight line with ab =60 metres and ac = 80 metres. a body moves from a to b at an average speed of 10 metres per second then from b to c in a time of 4 seconds and then returns to b. the average speed for the whole journey is 5 metres per second.
find:
1. the average speed of the body during the second stage of motion from b to c.
2. the average speed of the body in moving from a to c
3. the time taken for the 3rd stage of motion from c back to b
4. the average velocity for the complete motion