Question

A boy is moving around rectangular track with length 50m and width 20m. He moves around rectangular track twice and finally moving back to the starting point. If the total time by the boy is 100 seconds calculate his average speed and average velocity

Answer 1

Given:

A rectangular track

of length = 50m

and breadth = 20m

so the perimeter of the rectangle is

2(length +breadth)

=2(50+20)m

=140m

so,the perimeter of rectangle is 140 m

since, he moved around the track twice

so total distance is also twice

therefore,

total distance=2×140

total distance=280m

now to find the average speed of the boy

formula is (Avg. speed= total distance/total time)

(total time is given =100seconds)

so,(avg. speed = 280/100)m/s

avg. speed= 2.8 m/s

now to find average velocity

formula is (displacement/total time)

since,the boy came back to it's initial position

the displacement=0

and the total time is 100seconds

now , according to formula

avg. velocity=(0/100)m/s

so the avg.velocity =0m/s

so the answers are

avg. speed =2.8m/s

avg. velocity =0m/s

hope you understood