Work and Power in Biomechanics: Interactive Learning Quizzes

Question 1

Which of the following is the SI unit of power?

Accepted Answer

Watt

Answer

Kilogram-meter per second squared

Answer

Newton-meter per second

Answer

Joule

Question 2

A car engine produces 100 kW of power. If the car travels 100 km in 60 minutes, calculate the average power output of the engine.

Accepted Answer

27.8 kW

Answer

55.6 kW

Answer

100 kW

Question 3

Which of the following is an example of a situation where work is done but no power is generated?

Accepted Answer

Holding a heavy object at a constant height

Answer

Pulling a heavy object up a slope

Answer

Pushing a heavy object across a rough surface

Answer

Lifting a heavy object at a constant speed

Question 4

Which of the following is the definition of power?

Accepted Answer

The rate at which work is done

Answer

The amount of force applied to an object

Answer

The distance an object moves

Answer

The time it takes to do work

Question 5

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

Accepted Answer

Work = Power × Time; Energy = Power × Time

Answer

Work = Energy × Power; Power = Work × Time

Answer

Time = Energy × Power; Work = Power × Time

Answer

Energy = Work × Power; Time = Power × Work

Question 6

Which of the following is NOT a unit of power?

Accepted Answer

Joule (J)

Answer

Watt (W)

Answer

Kilowatt (kW)

Answer

Horsepower (hp)

Question 7

Which of the following is the SI unit of power, representing the rate at which work is done or energy is transferred?

Accepted Answer

Watt (W)

Answer

Newton (N)

Answer

Kilogram (kg)

Answer

Joule (J)

Question 8

Define work in physics and identify the factors involved in its calculation.

Accepted Answer

Work is the transfer of energy due to a force acting through a distance in the direction of the force. Factors involved are the force applied, the distance moved, and the angle between the force and displacement.

Answer

Work is the rate of change of energy.

Answer

Work is the change in energy of an object.

Question 9

Express the relationship between power, work, and time, and explain its significance.

Accepted Answer

Power = Work / Time. This equation highlights that power represents the rate at which work is done or energy is transferred over a specific time interval.

Answer

Time = Work / Power

Answer

Work = Power / Time

Answer

Time = Power - Work

Question 10

Distinguish between positive and negative work, providing examples to illustrate the difference.

Accepted Answer

Positive work occurs when the force applied and the displacement are in the same direction (e.g., lifting an object against gravity). Negative work occurs when the force and displacement are in opposite directions (e.g., lowering an object against gravity).

Answer

Positive work is done by an external force, while negative work is done by an internal force.

Question 11

Which device primarily converts electrical energy into mechanical energy?

Accepted Answer

Electric motor

Answer

Generator

Answer

Battery

Question 12

Identify the SI unit of power.

Accepted Answer

Watt

Answer

Kilogram

Answer

Newton

Answer

Joule

Question 13

Which factor does NOT influence the power output of a machine?

Accepted Answer

Temperature

Answer

Time

Answer

Distance

Answer

Force

Question 14

Identify a typical application of work and power principles in the field of sports.

Accepted Answer

Calculating the power output of a runner

Answer

Measuring the height of a jump

Answer

Determining the speed of a shot put

Answer

Estimating the force exerted by a weightlifter

Question 15

Explain the relationship between work, power, and energy.

Accepted Answer

Power equals Work divided by Time, and Energy equals Power multiplied by Time

Answer

Energy equals Work multiplied by Power

Answer

Work equals Power minus Energy

Answer

Power equals Energy divided by Work

Question 16

Identify the unit used to measure energy.

Accepted Answer

Joule

Answer

Hertz

Answer

Newton

Answer

Watt

Question 17

Identify a factor that influences the efficiency of a machine.

Accepted Answer

Friction

Answer

Humidity

Answer

Pressure

Answer

Temperature

Question 18

What is the SI unit of power?

Accepted Answer

Watts

Answer

Joules

Answer

Horsepower

Answer

Newtons

Question 19

The work done by a force is calculated by multiplying the force by the:

Accepted Answer

Displacement

Answer

Velocity

Answer

Acceleration

Question 20

An electric motor operates at a power of 750 W for 3 hours. How much energy does the motor use?

Accepted Answer

2700 kJ

Answer

270 kJ

Answer

750 kJ

Question 21

Which of the following is a non-renewable source of energy?

Accepted Answer

Fossil fuels

Answer

Hydropower

Answer

Solar power

Answer

Wind power

Question 22

Identify the scenario among the following that involves zero work being done:

Accepted Answer

Holding a heavy suitcase with an arm outstretched

Answer

Lifting a dumbbell off the ground

Answer

Running up a flight of stairs

Answer

Pushing a heavy box across the floor

Question 23

Which of these activities demands the greatest power output?

Accepted Answer

Sprinting a 100-meter race

Answer

Walking at a steady pace

Answer

Cycling uphill at a moderate speed

Question 24

Which statement best describes the relationship between work and energy?

Accepted Answer

Work is the transfer of energy from one form to another.

Answer

Energy is the rate at which work is done.

Answer

Work is a type of energy.

Question 25

A runner completes a 5 km race in 20 minutes. Which factor could potentially increase their power output during the race?

Accepted Answer

Running at a faster pace

Answer

Carrying a heavier backpack

Answer

Decreasing their stride length

Question 26

A cyclist applies a force of 50 N to the pedals while cycling at a constant speed. Calculate the work done by the cyclist over a distance of 100 meters.

Accepted Answer

5000 J

Answer

50 J

Answer

100 J

Question 27

A basketball player jumps vertically. Which of the following is true about the work done by the player's muscles during the jump?

Accepted Answer

The work done by the muscles is positive during the upward phase of the jump and negative during the downward phase.

Answer

The work done by the muscles is always positive during the jump.

Question 28

Two athletes, A and B, perform the same exercise. Athlete A completes the exercise in half the time of athlete B. What can be said about their power output?

Accepted Answer

Athlete A has a higher power output than athlete B.

Answer

Both athletes have the same power output.

Answer

Athlete B has a higher power output than athlete A.