Home
Class 11
PHYSICS
An aeroplane flies around a square field...

An aeroplane flies around a square field ABCD of each side 1000 km. Its speed along AB is `250 km h^(-1)` , along BC `500 km h^(-1)` , along CD `200 km h^(-1)` , and along DA 100 km `h^(-1)` , Its average speed (in km `h^(-1)` ) over the entire trip is

A

225.5

B

175.5

C

125.5

D

190.5

Text Solution

Verified by Experts

The correct Answer is:
D

Let `t_(AB) , t_(BC) , t_(TD) and t_(DA)` be the time taken by the aeroplane to go from A to B, B to C, C to D and D to A respectively.
`therefore t_(AB) = (1000km)/(250 km h^(-1)) = 4h`
`therefore t_(BC) = (1000km)/(500km h^(-1) ) = 2h`
`therefore t_(CD) = (1000km)/(200kmh^(-1) ) = 5h`
`therefore t_(DA) = (1000km)/(100kmh^(-1) ) = 10h`
Average speed ` = (1000km + 1000km + 1000km + 1000km)/(t_(AB) + t_(BC) + t_(CD) + t_(DA) = 4000/21 `
`190.5 kmh^(-1)`
Promotional Banner

Similar Questions

Explore conceptually related problems

On a 80 km track, a train travels 40 km with a uniform speed of 30 km h^(-1) . How fast must the train travel the next 40 km h^(-1) as to have average speed 40 km h^(-1) for the entire trip?

On a 100 km track, a train mvoes the first 50 km with a uniform speed of 50 km h^(-10 How fast must the train travel the next 50 km so as to have average speed 60 km h^(-1) for the entire trip ?

On a 60 km stretch of road a cyclist travels first 20 km at a unifrom speed of 20 km h^(-1) . How fast must he travel the reamaining distance so that his average speed is 10 km h^(-1) for the entire trip.

A car travels a distance of 560 km in 9.5 hours partly at a speed of 40 km h^(-1) and partly at 160 km h^(-1) . What is the distance it travel at the speed of 160 km h^(-1) ?

If the first one - third of q journey is travelled at 20 km h^(-1) , Next one - third at 40 km h^(-1) And the last one third at 60 km h^(-1) then the average speed for the whole journey will be

A body moves with a unifrom speed of 10 km h^(-1) for 2h. The average speed of the body is ______ km h^(-1)