Question

A man covers a distance of 20 m with 2m/s and 40m with 5m/s .find the average velocity of the man .

Answer 1

Answer:

Avg . v = 3.33 m/s

Explanation:

d1 = 20 m                   d2 = 40 m

s1 = 2 m/s                   s2 = 5 m/s

t1 = 10 s                       t2 = 8 s

Avg. v = (d1 + d1) / (t1 + t2)

= 60 / 18

= 3.33 m/s

Hope this helps.

Answer 2

Given:  Distance - d₁ = 20m

            speed - v₁ = 2m/s

           distance - d₂ = 40m

           speed - v₂ = 5m/s

To Find: Average velocity = v

Formula used :

• Average velocity = total distance (d) / total time(T)
• time = distance/velocity

Calcuting time taken - t₁ for $1^{st}$ Jorney with velocity = 2m/s

d₁ = 20

v₁ = 2m/s

time taken - t₁ = d₁/v₁

t₁ = 20/2

t₁ = 10s

Calculating time taken - t₂ for $2^{nd}$ Journey with velocity = 5m/s

d₂ = 40m

v₂ = 5m/s

t₂ = d₂/v₂

t₂ = 40/5

t₂ = 8s

Calculating total time taken - T

T = t₁ + t₂

T = 10 + 8

T = 18s

Calculating Total distance - d

d = d₁ + d₂

d = 20 + 40

d = 60m

Calculating Average velocity of the man - v

v = d/T

v = 60/18

v = 3.33 m/s

Hence, the average velocity of the man = 3.33m/s