Question

A man is chased by a dog who runs around a circular path of diameter 200m. He runs at a speed with which he covers the perimeter in 40 seconds. At the end of 2 minutes 20 seconds , what will be the distance covered by him? Also find the displacement at the end of the given period.

Pls answer fast..... it's urgent!!

Answer 1

radius=200m/2=100m

circumference=2^r=2x22/7x100=1100/7m

Distance =1100/7m or 157.14m

time=40sec

speed=d/t

1100/7 x 1/40= 55/14m per sec

another time=2mim20sec or 140sec

speed=55/14m per sec

therefore,distance=s X t

=55/14 x 140

=550m

distance covered after running

for the first time

=550/1100/7

=550x7/1100

=7/2m

=3whole1/2m

Therefore,3wholes=3circumference

therefore,the remaining distance would be the displacement=1/2 of the circumference=1/2 X 550/7 =275/7m or 78.57m

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