Intro to Physics G11

What is the unit of energy?

• Hertz

• Coulomb

• Joule

• Newton

Block A falls vertically from height h. Block B is thrown downward with initial speed v from height h. The blocks are identical. Which block hits the ground with the greatest speed?

• Block A

• Block B

• They reach the ground with the same speed

• Not enough information

What type of energy transformation takes place in dynamo?

• Potential energy to heat

• Mechanical energy to heat

• Mechanical energy to electrical energy

• Kinetic energy to heat

Why is an air-conditioner normally installed at the height in a room?

• So there is enough space for the other appliances

• Because hot air goes up and cold air goes down

• Because hot air goes up and mixed with cold air

Which type of energy is stored by moving objects?

• Potential energy

• Kinetic energy

• Thermal energy

• Electrical energy

What is one Joule equal to?

• kg m/s

• kg m/s²

• kg m²/s²

• kg m²/s

Which type of energy transfer can occur through a solid?

• Conduction

• Convection

• Radiation

A car uses energy stored in chemical form in petrol. When the engine is running this energy is transferred to other types of stored energy. Which of the following energy stores is useful?

• noise

• heat

• movement

• hot exhaust gases

Which of the statements about thermal radiation is false?

• It cannot travel through glass

• It can travel through a vacuum

• It travels at the speed of light

• It is absorbed by black objects better than shiny ones

The greenhouse effect occurs when greenhouse gases in a planet's atmosphere cause some of the heat radiated from the planet's surface to build up at the planet's surface. What kind of radiation that is trapped on the planet's surface?

• Ultraviolet

• X-ray

• Radio

• Infrared