work, energy, efficiency & power

Which of the statement below best describe work done?

• It is the ratio of energy output over the energy input

• It is the rate to do work

• It is the product of the force and the distance over which the force is applied

• It is the capacity to do work

What is the unit for work done, power and force?

• Joules, Watt and Newton

• Newton, Watt and Joules

• Joules, Newton and Watt

• Watt, Newton and Joules

Azri tries to lift a very heavy box but he was unable to move the box. Was there any work is done?

• Yes

• No

It took 500 N of force needed to push a car by 400 cm. How much work was done?

• 200,000 N

• 20 J

• 200 J

• 2000 J

Energy is the _______________ to do work

You are starting a car and start driving. What is the energy changes?

• Chemical energy to potential energy and kinetic energy

• Chemical energy to electrical energy and kinetic energy

• Electrical energy to chemical energy and kinetic energy

• Electrical energy to chemical energy and potential energy energy

_____________ refers to how fast a person or a machine work

Which of the formula below is correct to calculate Power? 

What is the law of conservation of energy?

Jenna is running with a velocity of 5 m/s. She has a mass of 65 kg. What is her kinetic energy?

• 325 J

• 162.5 J

• 3185 J

• 812.5 J