## Average Speed

“A car travels from A to B with a speed of 30km/h and returns back to A with a speed of 50km/h.Find distance,displacement,average speed and average velocity ifdistance between A and B is 100km.”

Distance 200 m

Displacement 0

Average velocity 0

Average speed =$\frac{2v_{1}v_{2}}{v_{1}+v_{2}}$ = 37.5 kmph

## Is the acceleration due to gravity different in south pole and north pole

“Is the acceleration due to gravity different in south pole and north pole?”

As per theory, acceleration due to gravity changes with altitude, depth and latitude.

If we consider that the variation of g with latitude is caused by rotation of earth only, then the value of g will be same for both north pole and south pole.

But, the change in the value of acceleration due to gravity with latitude is caused by the shape of earth too. So it depends your distance from the centre of earth when you are at north pole or south pole.

For calculations the polar radius is taken same at North as well as south pole. So, value of g can be taken the same for both poles.

## KVPY Interview

“I got selected for the kvpy interview which is going to be held shortly. i am interested in the field of aeronautics, but this comes under the field of applied science. wat do i do?”

No Worries. Just be original and update your basics. Your aptitude towards genuine research is more important. Study the field you like in deep and present well. All the best.

## Flies in a car

“while travelling, i have noticed some flies buzzing in front of me even if the car is going at a high speed…..

if the fly is stationary and moving freely the it can only do by running in the speed of the car. Howz that possible?

Any fly inside the car will have the same velocity as the car. Just imagine you are running and tossing a ball. You can see that the tossed ball returns to your hand though you were running.

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