G9-SCI-L10 Work and Energy

What is the scientific definition of work?

• Any physical or mental labor
• Any useful activity
• The product of force and displacement
• The exertion of effort

Which of the following activities does NOT involve work?

• Pushing a pebble
• Pulling a trolley
• Lifting a book
• Standing still with a heavy load

What is the unit of work?

• Joule
• Newton
• Watt
• Kilogram

When is work done by a force considered negative?

• When the force is applied in the same direction as the displacement
• When the force is applied opposite to the direction of displacement
• When the force is zero
• When the displacement is zero

What is the formula for calculating work done?

• Work done = force + displacement
• Work done = force - displacement
• Work done = force x displacement
• Work done = force / displacement

What is the unit of power?

• Joule
• Newton
• Watt
• Kilogram

What is the rate of doing work called?

• Energy
• Force
• Power
• Velocity

What is the law of conservation of energy?

• Energy can be created but not destroyed
• Energy can be destroyed but not created
• Energy can be transformed from one form to another
• Energy remains constant

What is the potential energy of an object at a height above the ground?

• mgh
• mg
• gh
• ms

What happens to the total energy of a system during energy transformation?

• It increases
• It decreases
• It remains the same
• It becomes zero