Question

an athlete runs on a circular track of radius r metres with a uniform speed and completes one revolution in t seconds.calcupate the distance and displacement in .
t/2s
3t/4s
pls tell the answer with explaination​

Answer 1

Answer:

the speed is eqaul to distnace and distance is ewaul to zero so speed is also equal to zero

Explanation:

sorry i need piitns

Answer 2

Answer:

In half a revolution (t/2 s), Distance = $\pi r$ and displacement = $2r$

In 3/4ths of a revolution (3/4t s), Distance = $\frac {3}{4} \times {2 \pi r} = \frac {3 \pi r}{2}$ and displacement is $\frac{\pi r}{2}$

Explanation:

Note-

Distance = actual path length

Displacement = shortest distance between start and end points

One revolution takes t seconds, so by unitary method half a revolution could be completed in t/2 seconds. Hence the first answer.

Similarly with the unitary method we can find that in 3t/4 seconds, 3/4 of a revolution could be completed.  Hence the second answer.

Drawing it out will help.