A boy moves 4 m towards east in 10 sec, then he turns right and move 3 m in 20 sec and reaches to a 10 m high pole. Then he climbs the pole in 20 sec. Find the average velocity of the boy.

CONCEPT:

Average velocity:

• The total displacement of the body divided by the time taken is called average velocity.

Displacement

• It is the shortest distance between the initial and final position of the particle.
• It is a vector quantity.

CALCULATION:

Given x₁ = 4 m, x₂ = 3 m, y = 10 m, t₁ = 10 sec, t₂ = 20 sec, and t₃ = 20 sec

• The total horizontal displacement of the boy on the ground is given as,

⇒ x = 5 m     -----(1)

• The resultant displacement of the boy is given as,

⇒ d = 5 m     -----(2)

• Total time is taken by the boy,

⇒ t = t₁ + t₂ + t₃

⇒ t = 10 + 20 + 20

⇒ t = 50 sec

• So the average velocity of the boy is given as,

• Hence, option 1 is correct.