Energy Transfers, and Thermal Energy transfer

Which is a method of energy transfer and not considered a store?

• Electrical
• Kinetic
• Gravitational
• Nuclear

When energy is dissipated it is

• Transferred to an object usefully
• It has been transferred to the surroundings in the form of heat
• It has been destroyed
• It has been created

When a force moves an object the energy has been transferred

• Electrically
• By heating
• Mechanically

When a person kicks a football

• Their chemical energy store increases, and the kinetic energy store of the football decreases
• Their thermal energy store increases and the kinetic energy store of the football increases
• Their chemical energy store decreases and the kinetic energy store of the football increases.

When a car brakes the energy change in energy stores which take place are:

• The kinetic energy of the air causes the car to stop
• The kinetic energy of the car increases and the thermal energy of the brakes increases
• The kinetic energy of the car decreases and the chemical energy of the car increases.
• The kinetic energy of the car decreases and the thermal energy of the brakes increases.

When a skydiver falls, what change in energy stores takes place

• They reduce their height and increase their speed.
• Their GPE store decreases and their Kinetic energy store increase
• Their GPE store increase and their Kinetic energy store increases
• Their gravity increases and thermal energy store of the surroundings decreases

For every 100J of energy transferred from their chemical energy store, a cyclist will generate 12J of kinetic energy. The remaining is transferred as heat to surroundings. What is their efficiency?

• 8.3%
• 833%
• 12%
• 78%

what is the amount of energy wasted by the electrical heater below?

• 50J
• 38J
• 12J
• 88J

what is the efficiency of the electrical heater below?

• 76%
• 100%
• 24%
• 130%

What type of energy transfer mainly takes place in a solid?

• Conduction
• Convection
• Radiation