person is running along a circular track of area625 Ď m2 (Ď-22/7

1.	person is running along a circular track of area625 Ď m2 (Ď-22/7) with a constant speed. Find thedisplacement in 15 seconds if he has to complete therace in 30 seconds.
Answer» area of circular track= 625π m^2 πr^2=625π r^2=625 π will get cancelled when it will go on L.H.S. r= √ 625 r=25 perimeter of circular track=2r =222/725 =4425/7 =1100/7 =157.14 m the person has to run distance of 157.14 m speed of person= distance/time distance=157.14 m time= 30 seconds speed= 157.14/30 =5.23 m/s displacement= speed time time=15 seconds speed=5.23 m/s displacement= 5.23*15 displacement in 15 seconds = 78.45 m

person is running along a circular track of area625 Ď m2 (Ď-22/7) with a constant speed. Find thedisplacement in 15 seconds if he has to complete therace in 30 seconds.

Answer»

area of circular track= 625π m^2

πr^2=625π

r^2=625 π will get cancelled when it will go on L.H.S.

r= √ 625

r=25

perimeter of circular track=2r

=2*22/7*25

=44*25/7

=1100/7

=157.14 m

the person has to run distance of 157.14 m

speed of person= distance/time

distance=157.14 m

time= 30 seconds

speed= 157.14/30

=5.23 m/s

displacement= speed* time

time=15 seconds

speed=5.23 m/s

displacement= 5.23*15

displacement in 15 seconds = 78.45 m