Work, Energy and Power

Question 1

What is the definition of work in physics?

Answer 1

Work is defined as the product of force and the distance over which it acts in the direction of the force.

Question 2

True or False: Work can be done when there is no movement.

Answer 2

False

Question 3

Fill in the blank: The unit of work is _____ in the International System of Units (SI).

Answer 3

joule

Question 4

What is the formula for calculating work?

Answer 4

Work = Force × Distance × cos(θ)

Question 5

What is energy?

Answer 5

Energy is the capacity to do work.

Question 6

Multiple Choice: Which of the following is a form of energy? A) Kinetic B) Potential C) Thermal D) All of the above

Answer 6

D) All of the above

Question 7

What is kinetic energy?

Answer 7

Kinetic energy is the energy possessed by an object due to its motion.

Question 8

What is the formula for kinetic energy?

Answer 8

Kinetic Energy = 1/2 mv², where m is mass and v is velocity.

Question 9

What is potential energy?

Answer 9

Potential energy is the energy stored in an object due to its position or configuration.

Question 10

What is the formula for gravitational potential energy?

Answer 10

Potential Energy = mgh, where m is mass, g is acceleration due to gravity, and h is height.

Question 11

True or False: Energy can be created or destroyed.

Answer 11

False

Question 12

What is the principle of conservation of energy?

Answer 12

The principle states that energy cannot be created or destroyed, only transformed from one form to another.

Question 13

What is power in physics?

Answer 13

Power is the rate at which work is done or energy is transferred.

Question 14

Fill in the blank: The unit of power is _____ in the International System of Units (SI).

Answer 14

watt

Question 15

What is the formula for power?

Answer 15

Power = Work / Time

Question 16

Multiple Choice: Which of the following units is equivalent to one watt? A) Joule/second B) Newton/meter C) Kilowatt-hour D) None of the above

Answer 16

A) Joule/second

Question 17

What is the relationship between work, energy, and power?

Answer 17

Work and energy are equivalent concepts; power measures how quickly work is done or energy is transferred.

Question 18

True or False: Power can be calculated using energy instead of work.

Answer 18

True

Question 19

What is mechanical energy?

Answer 19

Mechanical energy is the sum of kinetic and potential energy in an object.

Question 20

What is the work-energy theorem?

Answer 20

The work-energy theorem states that the work done on an object is equal to the change in its kinetic energy.

Question 21

Fill in the blank: In a closed system, the total energy _____ remains constant.

Answer 21

always

Question 22

What is the difference between renewable and non-renewable energy?

Answer 22

Renewable energy can be replenished naturally, while non-renewable energy is finite and cannot be replaced in a short time.

Question 23

What is thermal energy?

Answer 23

Thermal energy is the internal energy present in a system due to its temperature.

Question 24

Multiple Choice: Which of the following is NOT a form of energy? A) Light B) Sound C) Gravity D) Heat

Answer 24

C) Gravity

Question 25

What is efficiency in the context of energy?

Answer 25

Efficiency is the ratio of useful work output to total energy input, often expressed as a percentage.