Q-5. Give scientific reason: why the …

There are 2 resons for which the weight at equator is less that of poles :

1. Rotation of the earth:

The general equation for gravitational acceleration at various latitudes can be given as:

• r is radius of earth ,  is angular velocity of earth and  is angle of latitude.

Now, at equator , value of  =0°, but at poles = 90° , so we can say:

• Since the gravitational acceleration at the equator is less than that of the poles an object will have lesser weight at the equator.

2. Spheroidal shape of earth:

• The it is not completely spherical and the radius at the equator is slightly greater as compared to that of the poles.

• That is why , the gravitational acceleration at the equator is slightly less as compared to that of the poles.

• And hence the weight is lesser at the poles.