Question

circle track has circumference of 314 metre a cyclist moves along the circumference and completes one round in half an hour find his distance and displacement after 45 minutes​

Answer 1

Explanation:

The cyclist needs half an hour to complete one round.

So after 30 minutes cyclist will complete one round. So now 15 minutes are left out of 45 minutes which is exactly half the time taken to complete one round.

So the cyclist will complete half round which is 157 m.

Therefore the total distance covered will be 314 + 157 = 471 m.

Displacement is the distance of the straight path between the current position and initial position.

After 45 min cyclist will be exactly at the opposite diametric point.

Since circumference = 2*pie*r = 314(for given problem)

2*r = 100

Displacement = diameter = 2*r = 10

Answer 2

Explanation:

since the circumference(314m) is the distance that the cyclist moves in half an hour(30 minutes), then after 45 minutes his displacement will be half the track as if he completes one round in 30 minutes then in extra 15 minutes(45-30=15) he will go half the track i.e.157m and his distance after 45 minutes will be 314m+157m=471m