Can there be a physical quantity that has no units and no dimensions?Yes, Strain has no unit and no dimensions.

Can a body have zero velocity and non-zero acceleration?Ans: Yes. A body thrown vertically upwards has zero velocity at its highest point. But at the highest point it has an acceleration equal to acceleration due to gravity.

Is it possible to have a negative value for the scalar product of two vectors?Ans: Yes. If the angle between the two vectors lies between 90° and 270°, their scalar product will be negative.

When an air bubble rises in water, what happens to its potential energy?Ans: Potential energy of an air bubble decreases because work is done by upthrust on the bubble.

Can there be a physical quantity that has no units and no dimensions?

ReplyDeleteYes, Strain has no unit and no dimensions.

Can a body have zero velocity and non-zero acceleration?

ReplyDeleteAns:

Yes. A body thrown vertically upwards has zero velocity at its highest point. But at the highest point it has an acceleration equal to acceleration due to gravity.

Is it possible to have a negative value for the scalar product of two vectors?

ReplyDeleteAns:

Yes. If the angle between the two vectors lies between 90° and 270°, their scalar product will be negative.

When an air bubble rises in water, what happens to its potential energy?

ReplyDeleteAns:

Potential energy of an air bubble decreases because work is done by upthrust on the bubble.