Chapter 7

Question 1

Mechanical energy storage

Answer 1

Mostly stored via tension of compression

Question 2

Coiled Springs

Answer 2

Used in some clocks, watches, and wind up toys

They use tension to store mechanical energy through the winding process

It’s then slowly released via cogs, gears, or other mechanisms to cause controlled movement

Question 3

Suction hopper toys

Answer 3

Use compression to store mechanical power, and jump into the air when the compression is released

Question 4

Pneumatics and Hydraulics

Answer 4

Pneumatics store gas/air under pressure, whereas hydraulics store water/oil/other liquids. Both use mechanical power

Pneumatics>Hydraulics:
Commonplace for controlling production lines
Used with inflatable structures and air guns
Accurate, efficient and cheap

Pneumatics

Question 5

Kinetic energy storage

Answer 5

Kinetic energy is the energy involved in motion

When an object is not in motion, it instead has potential energy.

This is converted into kinetic energy when a fore, such as gravity, acts on an object - causing it to move

Question 6

Things that store potential energy (to then be converted into kinetic energy) include

Answer 6

Springs

Elastic bands

Balloons

Crossbows

Question 7

Flywheel

Answer 7

A giant wheel that spins, generating kinetic energy

That energy can then be converted into electricity through a generator

Flywheels can provide continuous energy when the primary source is discontinuous, or deliver bursts of energy by releasing all the stored energy at a go

A generator driven in reverse acts as a motor, which can be used to speed up the flywheel when demand is higher

Question 8

Chemical energy storage

Answer 8

Can provide electrical power when stored in batteries, which is its main storage place

A battery contains one or more cells, with each typically providing 1.5 volts

Proper disposal of batteries is important, as they contain toxic electro chemicals and some metals that are harmful to the environment
Sizes of batteries in ascending order:
AAA, AA, PP3, C, D

Question 9

Alkaline battery

Answer 9

Have a higher capacity for their size compared to traditional acid based batteries

This is due to the dense manganese dioxide inside them that uses less space to produce the same amount of power

Question 10

Rechargeable batteries

Answer 10

Have a voltage of around 1.2V, and is used in many electrical devises such as mobile phones