Question

Jack and Jill exercise in a 25.0 m long swimming pool. Jack swims 9 lengths of the pool in 161.3 s (2 min and 41.3 s) , whereas Jill, the faster swimmer, covers 10 lengths in the same time interval. Find the average velocity and average speed of each swimmer.

Jack's average velocity: ___m/s

Jack's average speed: ____m/s

Jill's average velocity: _____m/s

Jill's average speed: _______m/s

Answer 1

Length of the pool=25m

Now the thing we need to consider here is,

Average Speed(v_avg)=(total distance covered)/(total time taken)

while, Average Velocity()=(net displacement)/(total time taken)

So, For Jack-

initial position=0, number of rounds=9, hence final position=25m

net distance = 25*9=225m , total time taken=161.3s

Hence, v_avg=225/161.3 = 1.395m/s

net displacement= final position- initial position= 25-0=25m

=25/161.3=0.155m/s.

Now, For Jill-

initial position=0, number of rounds=10, hence final position=0

net distance = 25*10=250m , total time taken=161.3s

Hence, v_avg=250/161.3 = 1.55m/s

net displacement= final position- initial position= 0-0=0m

=0/161.3=0m/s