Question

About flies north at 20 metre per second from 15 second dress for 5 second and then fly south at 25 metre per second for 10 seconds for the whole trip find the average speed

Answer 1

Correct question: A bird flies north at 20m/s for 15 sec. It rests for 5 sec and then flies south at 25m/s for 10 secs. For the whole trip, find average speed?

Answer:

18.33 m/s

Explanation:

Given that ;

At first bird flies to north, here

Speed, S₁ = 20 m/s

Time, t₁ = 15 secs

Distance, d₁ = S₁ * t₁

⇒ d₁ = 20 * 15

⇒ d₁ = 300 m

Then, bird rest for 5 secs, t₂ = 5 secs

And, after that flies to south,

Speed, S₂ = 25 m/s

Time, t₃ = 10 secs

Distance, d₂ = S₂ * t₂

⇒ d₂ = 25 * 10

⇒ d₂ = 250 m

Total distance = (300 + 250)m

⇒ D = 550 m

Total time taken = (15 + 5 + 10)secs

⇒ T = 30 secs

$\sf Average \: speed = \frac{total \: distance}{total \: time \: taken} \\ \\ \sf Average \: speed = \frac{550}{30} = 18 .33$

Hence, the average speed is 18.33 m/s.