3N Energy Quiz

What is the SI unit for energy?

• kg

• J

• K

• N

Answer explanation

The SI unit for energy is 'J' which stands for Joules. It is commonly used to measure energy in various fields of science and engineering.

Which type of energy is related to moving objects?

• Potential Energy

• Thermal Energy

• Electrical Energy

• Kinetic Energy

Answer explanation

Moving objects are related to Kinetic Energy, which is the energy of motion.

Which type of energy is related to the height of an object?

• Kinetic Energy

• Chemical Potential Energy

• Elastic Potential Energy

• Gravitational Potential Energy

Answer explanation

Gravitational Potential Energy is related to the height of an object as it depends on the object's position in a gravitational field.

The formula for Kinetic Energy is .....

• 1/2 mv

• 1/2 mv²

• 1/2 m²v²

• 1/4 m²v²

Answer explanation

The correct formula for Kinetic Energy is 1/2 mv^2, where m is mass and v is velocity.

Qamar goes for a run after eating his breakfast. Which energy change takes place as he accelerates?

• Chemical potential energy is converted to kinetic energy.

• Chemical potential energy is destroyed.

• Kinetic energy is converted to chemical potential energy.

• Kinetic energy is destroyed.

Answer explanation

Chemical potential energy is converted to kinetic energy.

Jackie pushes a box along the floor. The total constant horizontal force on the box is 80 N. The work done is 100 J. Friction is negligible. How far does the box move?

• 0.80 m

• 1.25 m

• 1.80 m

• 2.50 m

Answer explanation

The work done is equal to the force multiplied by the distance. Therefore, distance = work / force = 100 J / 80 N = 1.25 m.

Zachary pedals to the top of Bukit Timah hill at constant speed. Which type of energy decreases as he pedals?

• chemical potential energy

• elastic potential energy

• gravitational potential energy

• kinetic energy

Answer explanation

As Zachary pedals to the top of Bukit Timah hill, the chemical potential energy stored in his muscles is being converted into kinetic energy, so chemical potential energy decreases.

Zachary pedals to the top of Bukit Timah hill at constant speed. Which type of energy increases as he pedals?

• chemical potential energy

• elastic potential energy

• gravitational potential energy

• kinetic energy

Answer explanation

As Zachary pedals to the top of Bukit Timah hill, his gravitational potential energy increases due to his elevation gaining, which is directly related to the height of the hill.

Which equation for calculating gravitational potential energy is correct?

• mg/h

• m/gh

• mgh

• gh/m

Answer explanation

Choose mgh as the correct equation for calculating gravitational potential energy.

Nihal lifts 20 bricks, each weighing 6 N. What other information is needed to calculate the work done in lifting the bricks?

• the height he lifts the bricks

• the mass of the bricks

• the time taken to lift the bricks

• the volume of the bricks

Answer explanation

The height he lifts the bricks is needed to calculate the work done in lifting the bricks.