A particle moves inside a circular glass tube under the influence of a tangential force of constant magnitude F (Figure 6.78). Explain why we cannot associate a potential energy with this force. How is this situation different from the case of a block on the end of a string, which is swung in a circle?

Short Answer

Expert verified

The block will gain both kinetic and potential energy which it swung in the circle

Step by step solution

01

Identification of given data

The given data can be listed below,

  • The magnitude of the tangential force isF.

  • The particle is moving inside a glass tube.

02

Concept/Significance of potential energy

Potential energy is described as the energy of matter that, when released, will spontaneously move or do work owing to the force of other matter, such as gravity.

03

Determination of How is the situation different from the case of a block on the end of a string, which is swung in a circle.

Only conservative forces are valid, and potential energy functions specify them. Potential energy cannot be related to this force because it is not conservative. As the force is in the tangential direction, the ball cannot be limited to a specific route.

When the block of massmis attached to the end of the string, due to the oscillations, it will gain both kinetic and potential energy because when its velocity reaches the maximum, it will have kinetic energy. At the lowest velocity, it will gain potential energy.

Thus, the block will gain both kinetic and potential energy which it swung in circle.

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