Circuits

Question 1

What is the name of this component?

Answer 1

Resistor

Question 2

Is a thermistor a digital or an analogue device?

Answer 2

Analogue

Question 3

What unit is resistance measured in?

Answer 3

Resistance is measured in ohms.

Question 4

Which quantity is represented by the symbol I?

Answer 4

I = current

Question 5

Name as many different types of energy as possible.

Answer 5

Kinetic, potential, electrical, chemical, light, heat, sound, nuclear

Question 6

What is the name of this component?

Answer 6

L.D.R. (light-dependent resistor)

Question 7

What is the name of this component?

Answer 7

Variable resistor

Question 8

What does a.c. stand for, and what does it mean?

Answer 8

a.c. stands for alternating current, which means the current changes direction every fraction of a second.

Question 9

Is a loudspeaker an input or an output device?

Answer 9

Output device

Question 10

What unit is voltage measured in?

Answer 10

Voltage is measured in volts (V).

Question 11

Is a relay a digital or an analogue device?

Answer 11

Digital

Question 12

Is a buzzer an input or an output device?

Answer 12

Output device

Question 13

What is the name of this component?

Answer 13

Cell

Question 14

Is a lamp a digital or an analogue device?

Answer 14

Analogue

Question 15

Round off this number to 3 significant figures.

3.14159

Answer 15

3.14159 rounded off to 3 significant figures is

3.14

Question 16

How many pencils are there?

Answer 16

Question 17

Is a switch an input or an output device?

Answer 17

Input device

Question 18

How could the resistance of a component be found from this graph?

Answer 18

The resistance could be found by

(a) calculating the gradient of the graph
(b) choosing a point on the graph and calculating voltage / current

Question 19

Is a motor a digital or an analogue device?

Answer 19

Analogue

Question 20

What does the prefix m stand for?

Answer 20

m stands for milli

milli = x 10^-3

Question 21

Is a microphone an input or an output device?

Answer 21

Input device

Question 22

Is a buzzer a digital or an analogue device?

Answer 22

Digital

Question 23

What does the prefix k stand for?

Answer 23

k stands for kilo

kilo = x 10³

Question 24

Is a motor an input or an output device?

Answer 24

Output device

Question 25

How many types of electric charge are there, and what are their names?

Answer 25

There are **two types** of **electric charge** - **positive** and **negative**

Question 26

Is an **LDR** an **input** or an **output** device?

Answer 26

**Input device**

Question 27

Is a **switch** a **digital** or an **analogue** device?

Answer 27

**Digital**

Question 28

Which quantity is represented by the symbol **V**, in the equation shown ?

Answer 28

**voltage** | (or **potential difference**)

Question 29

What is the definition of **current**?

Answer 29

**Current** is how much electrical charge flows (past a point) in one second.

Question 30

Is a **lamp** an **input** or an **output** device?

Answer 30

**Output device**

Question 31

What is the name of this component?

Answer 31

**Lamp**

Question 32

Describe how to use an **ammeter** to **measure the current** in a component.

Answer 32

An **ammeter** must be connected **in series** with a component.

Question 33

Why does an **L.E.D.** always have a resistor connected in series with it?

Answer 33

An L.E.D. always has a resistor connected in series with it to **protect the L.E.D.** The resistor will **limit the current in the L.E.D.**

Question 34

Is a **thermistor** an **input** or an **output** device?

Answer 34

**Input device**

Question 35

Describe how to use a **voltmeter** to **measure the voltage** across a component.

Answer 35

A **voltmeter** must be **connected in parallel** with a component.

Question 36

Round off this number to **3 significant figures**. ## Footnote 1,526.33

Answer 36

1,526.33 rounded off to 3 significant figures is **1,530** (the '2' has been rounded **up** to 3)

Question 37

What **unit** is **current** measured in?

Answer 37

Current is measured in **amperes** (**A**).

Question 38

Is a **LDR** a **digital** or an **analogue** device?

Answer 38

**Analogue**

Question 39

Which quantity is represented by the symbol **R**?

Answer 39

**R** = **resistance**

Question 40

What is the name of this component?

Answer 40

**L.E.D. (light-emitting diode)**