C7

Question 1

Energy is

Answer 1

Ability to do work

Question 2

Forms of energy

Answer 2

Light, electrical, heat, potential, nuclear, sound, kinetic, chemical

Question 3

Earth receives what from the Sun

Answer 3

Heat and light energy

Question 4

Sources of energy

Answer 4

Sun, waves, water, wind, biomass, radioactive substances, geothermal, fossil fuel

Question 5

Electrostatics

Answer 5

Electric charges that are stationary

Question 6

What will happen when two different insulating materials such as glass and silk are rubbed against one another

Answer 6

When seperated, friction between the two objects will cause one of the objects to become positively charged while the other, negatively charged

Question 7

Electroscope

Answer 7

Detect the existance of electric charges

Question 8

Occurrence of lightning

Answer 8

When negative charges in the bottom of the cloud are attracted to the positive charges in the ground

Question 9

How to reduce the electrostatic charges at the body of the tanker

Answer 9

Metal chain. Electrostatic chargers will flow from the body of the tanker to the ground through the metal chain, without producing any sparks

Question 10

Electric current (I)

Answer 10

Rate of flow of electrons

Question 11

Unit for electric current

Answer 11

Amphere(a)

Question 12

Electric current is measured using

Answer 12

Ammeter

Question 13

Voltage (v)

Answer 13

Energy needed to move electrons between to points

Question 14

Unit for voltage (v)

Answer 14

Volt (V)

Question 15

Voltage is measured using

Answer 15

Voltmeter

Question 16

Resistance

Answer 16

The ability to resist electric current

Question 17

Unit for resistance

Answer 17

Ohm

Question 18

Electric current is made up of

Answer 18

Source of electrical energy, electrical components, connecting wire

Question 19

Electrical components

Answer 19

Switch, dry cell, bulb, resistor, voltmeter, ammeter, galvanometer

Question 20

Types of electric circuit

Answer 20

Series, parallel

Question 21

SCA

Answer 21

Itotal = I1=I2

Question 22

PCA

Answer 22

Itotal=I1+I2

Question 23

SCV

Answer 23

Vtotal=V1+V2

Question 24

PCV

Answer 24

Vtotal=V1=V2

Question 25

SCR

Answer 25

Rtotal=R1+R2

Question 26

PCR

Answer 26

1/Rtotal=1/R1+1/R2

Question 27

Pros of series circuit

Answer 27

Same amount of electric charge, all electrical components are controlled by the same switch

Question 28

Cons of series circuit

Answer 28

One bad, all bad.,

Question 29

Pros of parallel circuit

Answer 29

All can be controlled separately, one bad will still be ok

Question 30

For a room, which circuit is better. Why.

Answer 30

Parallel, can be controlled separately. One bad, all still ok

Question 31

Electric magnet

Answer 31

Electric conductor

Question 32

Electricmagnet eg

Answer 32

straight wire, a coiled wire or a solenoid

Question 33

Electromagnet becomes a

Answer 33

temporary magnet when an electric current flows through the electric conductor

Question 34

Strength of the magnetic field of an electromagnet

Answer 34

Amount of the electric current that flows

Question 35

Advantage of an electromagnet

Answer 35

strength of its magnetic field can change according to the amount of the electric current that flows through the electromagnet.