Electricity

Question 1

What charge is on an object if you remove electrons or added

Answer 1

Remove electrons from an object and the object is positive.

Add extra electrons to an object and the object is negative.

Question 2

How do you remove or add electrons to an object

Answer 2

Friction

Question 3

Explain the method to the experiment to demonstrate the force between charged objects

Answer 3

Rub a polythene rod with a woollen cloth and then hang it from a clamp (polythene rod is negatively charged.)

Rub a Perspex rod with a woollen cloth. (Perspex rod is positively charged.)

Bring the Perspex rod near the polythene rod.

Now rub another polythene rod with a woolen cloth and bring near to the hanging polythene rod

Question 4

What conclusion can be drawn from the results of the experiment to demonstrate the force between charged objects

Answer 4

Like charged objects repel each other.

Oppositely charged objects attract each other.

Question 5

Explain an insulator of electricity

Answer 5

A material through which charge cannot flow.

Question 6

Explain a conductor in terms of electricty

Answer 6

A material a charge can travel along.

Question 7

Explain how a lightning rod works

Answer 7

A lightning rod is made of a good conducting metal. A sharp, metal rod is placed above the tallest part of the building. If lightning hits the metal rod, the electrons travel to the ground along the metal conductor and the building is undamaged.

Question 8

What is current measured in?

Answer 8

Current is measured in the ampere (A)

Question 9

Explain current electricity

Answer 9

Current electricity is the flow of electrons along a wire.

Question 10

Explain voltage

Answer 10

Voltage is a measure of the ability of the electrons to do a particular task.

Question 11

What is another name for voltage

Answer 11

Potential difference

Question 12

What is the unit of voltage

Answer 12

Voltage is measured in the volt (V).

Question 13

Explain resistance

Answer 13

The opposition to the flow of electrons is called resistance.

Question 14

What is the measure of resistance

Answer 14

Resistance is measured in the

ohm, Ω.

Question 15

How would you set up a circuit to test electrical conduction in a variety of materials and classify each material as a conductor or insulator

Answer 15

Set up circuit with switch,6V battery, light bulb, space to place varying material in.

Question 16

Name some substances you could test the electrical conduction in and classify each as a conductor or insulator

Answer 16

metal key, iron nail, steel wool, piece of wood, piece of plastic and glass

Question 17

How would you set up a circuit for the experiment To measure current, potential difference (voltage) and resistance and to establish the relationship between them (Ohm’s law)

Answer 17

Using 6V battery, ammeter, voltmeter, resistor, variable resistor and connecting wires

Question 18

State Ohm’s law

Answer 18

The potential difference (voltage) is directly proportional to the current. This is called Ohm’s law.

Question 19

What is the triangle to remeber formula for voltage, current and resistance

Answer 19

Valeries instant rice
V
——-
I x R

Question 20

Explain the circuit if two bulbs in parallel and the results of taking out a bulb at a time

Answer 20

The current from the battery divides, some passing through one bulb and the rest passing through the second bulb. If the bulbs are identical the current divides into two equals amounts. Each bulb would then get the same current. If one bulb is taken out the other bulb will light.