A bricklayer lifts 30 kg of bricks onto a high scaffolding platform.

He lifts 10 kg of bricks at a time and repeats this three times. A mechanical hoist is also capable of lifting all 30 kg of bricks at once onto the same scaffolding platform.

State the term used for the energy gained by the bricks when they are lifted onto the platform.

Compare the energy gained by the 30 kg of bricks when lifted by the bricklayer with the energy gained when they are lifted by the mechanical hoist.

Four physical scenarios are described below. Identify the scenarios in which mechanical work is done by the specified entity:

1. A book lies resting on a flat library table.
2. A horse pulls a cart along a horizontal farm track.
3. A student holds a heavy backpack stationary on their shoulders.
4. An archer pulls back a bowstring to prepare an arrow.

Electrical appliances transfer energy. Match each of the following electrical appliances with its primary useful energy output:

• Appliances: Electric heater, Loudspeaker, Electric blender
• Energy Outputs: sound, light, thermal, kinetic, chemical