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#### Rahul runs around a rectangular shaped ground of length =70 metres andwidth = 40 metres. He ran two laps around the rectangular ground, and finally ran back to the starting point. If his total time to run the track is 120 seconds, find the average speed and the average velocity.Option: 1 Average Speed = 2.8 m/s and Average Velocity = 2  Option: 2 Average speed = 5.2 m/s and Average Velocity = 4  Option: 3 Average Speed = 2.3 m/s and Average Velocity =0  Option: 4 Average Speed = 4 m/s and Average Velocity =5

Given that:

Length of the rectangular ground = 70 metre

Width of the rectangular ground = 40 metre

Time taken = 120 seconds

Now,

The perimeter of the rectangle, that is to say the distance of a circle

= 2(70 metres) + 2 (40 metres)

= 140 metres + 80 metres

= 220 metres

When Rahul circles the rectangle twice = 2(220 meter)

= 440 metres

Therefore

Distance = 440 metres

Displacement = 0 metres.

Displacement is zero because Rahul returned to the starting point.

Now,

Average Speed =  $\frac{distance}{elapsed\ time}$

= $\frac{280}{120}$  metres.

= 2.3 metre/ second

And,

Average speed =  $\frac{displacement}{elapsed\ time}$

$\frac{0}{120}$ seconds

= 0 seconds

If the displacement is zero, the velocity can be zero.

However, the body must move a certain distance and return to the initial position.