Question

A body of mass m moving along a straight line covers half the distance with a speed of 2m/s . The remaining half of the distance is covered in two equal time intervals with a speed of 3 m/s and 5m/s respectively. The average speed of the particle for the entire journey is ?

Answer 1

average speed cover into equal time intervals = 5+3/2=4
average speed of particle in entire journey =
2/v = 1/2 + 1/4
2/v =3/4
v= 8/3 m/s
hope it helps

Answer 2

The average speed of the particle in entire journey is 8/3ms-1.

Mass of the body = m (GIven)

Speed when half distance is covered = 2m/s (GIven)

Equal time intervals =  3 m/s and 5m/s (GIven)

Let the total distance traveled by the body be = S

Let the time taken by the body to travel first half of the distance be = t-1

vavg = Total Distance / Total Time

t1 = S/2 /2 = S/4

vav = S / t-1 + 2t2

= S / S/4 + 2 (S/16)

= 8/3

Thus, the average speed of the particle is 8/3ms-1