In terms of the change in kinetic energy ($\Delta K$) and the change in potential energy ($\Delta U$), which expression gives the work done by all nonconservative forces ($W_{\text{nc}}$) acting on a system?

A) $W_{\text{nc}} = \Delta K - \Delta U$

B) $W_{\text{nc}} = \Delta U - \Delta K$

C) $W_{\text{nc}} = -(\Delta K + \Delta U)$

D) $W_{\text{nc}} = \Delta K + \Delta U$

When an object is subject to a conservative force, in which direction does this force always act relative to the system's potential energy distribution?

A) Toward regions of higher potential energy

B) Toward regions of lower potential energy

C) In the direction perpendicular to changes in potential energy

D) In the direction that maintains a constant potential energy

When only conservative forces do work on an object within an isolated system, how does the total mechanical energy of the system behave?

A) It continuously decreases because energy is dissipated into thermal energy.

B) It fluctuates unpredictably depending on the geometric path taken by the object.

C) It increases whenever kinetic energy increases and decreases whenever potential energy increases.

D) It remains constant because energy is only transferred between kinetic and potential forms.

An object slides across a rough horizontal surface and slows to a stop under the action of kinetic friction. What is the sign of the work done by kinetic friction on the object, and how does the thermal energy of the object-surface system change?

A) The work done is negative, and the thermal energy increases.

B) The work done is negative, and the thermal energy decreases.

C) The work done is positive, and the thermal energy increases.

D) The work done is zero, and the thermal energy remains constant.

A particle moves between two points under the influence of a conservative force. If the conservative force does positive work on the particle, how does the potential energy associated with this force change?

A) It increases by an amount equal to the work done by the force.

B) It remains constant because the force is conservative.

C) It increases or decreases depending on the path taken between the two points.

D) It decreases by an amount equal to the work done by the force.

A block is moved from an initial position to a final position along several different trajectories in a region where both gravity and kinetic friction act. Which of the following quantities is independent of the trajectory taken between these two positions?

A) The work done by kinetic friction on the block

B) The total work done by all acting forces on the block

C) The work done by the gravitational force on the block

D) The thermal energy generated due to friction along the path

Which of the following forces causes a change in the total mechanical energy of a system when it does work on an object?

B) Ideal spring restoring force

Which of the following statements correctly describes a defining property of a conservative force?

A) The total work done by the force on an object moving around any closed path is zero.

B) The work done by the force between two fixed endpoints depends on the specific path taken.

C) It continuously dissipates the mechanical energy of an isolated system into thermal energy.

D) A potential energy function cannot be defined for the work performed by the force.

Conservative and nonconservative forces Knowledge-Based Download PDF

Physics · Energy, Work & Power · Physics · Forms of Energy & Conservation

10 Physics practice questions on Conservative and nonconservative forces. Questions that assess core concepts and understanding.

Questions

1.
In terms of the change in kinetic energy ( $\Delta K$ ) and the change in potential energy ( $\Delta U$ ), which expression gives the work done by all nonconservative forces ( $W_{\text{nc}}$ ) acting on a system?
- A) $W_{\text{nc}} = \Delta K - \Delta U$
- B) $W_{\text{nc}} = \Delta U - \Delta K$
- C) $W_{\text{nc}} = -(\Delta K + \Delta U)$
- D) $W_{\text{nc}} = \Delta K + \Delta U$
2.
When an object is subject to a conservative force, in which direction does this force always act relative to the system's potential energy distribution?
- A) Toward regions of higher potential energy
- B) Toward regions of lower potential energy
- C) In the direction perpendicular to changes in potential energy
- D) In the direction that maintains a constant potential energy
3.
When only conservative forces do work on an object within an isolated system, how does the total mechanical energy of the system behave?
- A) It continuously decreases because energy is dissipated into thermal energy.
- B) It fluctuates unpredictably depending on the geometric path taken by the object.
- C) It increases whenever kinetic energy increases and decreases whenever potential energy increases.
- D) It remains constant because energy is only transferred between kinetic and potential forms.
4.
An object slides across a rough horizontal surface and slows to a stop under the action of kinetic friction. What is the sign of the work done by kinetic friction on the object, and how does the thermal energy of the object-surface system change?
- A) The work done is negative, and the thermal energy increases.
- B) The work done is negative, and the thermal energy decreases.
- C) The work done is positive, and the thermal energy increases.
- D) The work done is zero, and the thermal energy remains constant.
5.
A particle moves between two points under the influence of a conservative force. If the conservative force does positive work on the particle, how does the potential energy associated with this force change?
- A) It increases by an amount equal to the work done by the force.
- B) It remains constant because the force is conservative.
- C) It increases or decreases depending on the path taken between the two points.
- D) It decreases by an amount equal to the work done by the force.
6.
A block is moved from an initial position to a final position along several different trajectories in a region where both gravity and kinetic friction act. Which of the following quantities is independent of the trajectory taken between these two positions?
- A) The work done by kinetic friction on the block
- B) The total work done by all acting forces on the block
- C) The work done by the gravitational force on the block
- D) The thermal energy generated due to friction along the path
7.
A potential energy function can be defined only for a conservative force. Which of the following forces can have an associated potential energy function?
- A) Kinetic friction force
- B) Air drag force
- C) Gravitational force
- D) Viscous damping force
8.
An object moves along a closed path and returns to its initial position. Which of the following forces can do non-zero net work on the object over this complete round trip?
- A) Ideal spring force
- B) Kinetic frictional force
- C) Gravitational force
- D) Electrostatic force
9.
Which of the following forces causes a change in the total mechanical energy of a system when it does work on an object?
- A) Gravitational force
- B) Ideal spring restoring force
- C) Kinetic friction force
- D) Electrostatic force
10.
Which of the following statements correctly describes a defining property of a conservative force?
- A) The total work done by the force on an object moving around any closed path is zero.
- B) The work done by the force between two fixed endpoints depends on the specific path taken.
- C) It continuously dissipates the mechanical energy of an isolated system into thermal energy.
- D) A potential energy function cannot be defined for the work performed by the force.

AI study assistant

Practice questions

Topic explanations

Download question PDFs

Conservative and nonconservative forces Knowledge-Based Download PDF

Questions

Quick Links

Terms of Service

Unlock the power of AI

AI study assistant

Practice questions

Topic explanations

Download question PDFs

Provide additional feedback

Why do you like this response?

Provide your feedback

Share

Questions