Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

science > Science chapter 13 > Flashcards

Science chapter 13 Flashcards

(55 cards)

Start Studying
1
Q

An electrical system comprises of

A

-connecting wires
-dry cell, one
-dry cells, two in
series
-switch (open)
-switch (closed)
-light bulb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The SI unit of current is the

A

ampere (A). One ampere of
current means that one unit charge flows in one second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

We measure current using an

A

ammeter, + to +, - to -

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is an electric current

A

An electric current is the rate of flow of electric charge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does conventional current flow

A

current flows
from the positive terminal of a battery to
the negative terminal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does the electron current flow

A

it flows from the negative to the
positive terminal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

An electric current can flow only
when there is a

A

potential difference

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

An ammeter must be connected in

A

series in a
circuit.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the potential difference between any two points

A

it is the amount of energy needed to move one unit of electric charge from one point to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The SI unit of potential difference is

A

Volt (V)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The more energy needed to move a charge
between two points in a circuit, the greater the
potential difference between the two points.

A

the greater the
potential difference between the two points.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

We measure potential difference using a

A

voltmeter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The voltmeter must be connected in

A

parallel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the resistance of a component is the ratio of
the potential difference across it to the current
flowing through it.

A

It is the ratio of
the potential difference across it to the current
flowing through it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the SI unit of resistance

A

ohm (Ω).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The greater the ratio of V to I, the

A

greater the
resistance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The resistance of an object depends on factors such as

A

the cross-sectional area, length and type of material the
object is made of.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are fixed resistors

A

the
resistance of the circuit cannot be changed
unless the resistors themselves are changed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

the resistance of the circuit cannot be changed
unless

A

the resistors themselves are changed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

In a series circuit, the electrical components are joined one after another to form a single loop. Electric current passes through a single path in a series circuit.

A

one after another to form a single loop. Electric current passes through a single path in a series circuit.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

A variable resistor or rheostat allows us to

Study These Flashcards
A

adjust the resistance in a circuit.

15
Q

In a parallel circuit, the electric current is divided into

Study These Flashcards
A

into branches. Electrical components (e.g. bulbs) are connected in each branch. Electric current passes through all branches of a parallel circuit.

15
The higher the resistance, the
dimmer the bulb
16
When the rheostat slider is on the left, the
short resistance wire offers low resistance.(bulb is brighter)
17
In a series circuit, the current at every point is ... the sum of the potential difference across each component is equal to ... Vε = V1 + V2 + V3 + … + Vn
the same; , the potential difference across the whole circuit.
18
In a series circuit, the effective resistance R is the R = R1 + R2 + . . . + R
sum of all the resistances.
19
In a series circuit, the effective resistance is always
greater than the largest of the individual resistances.
20
V = IR
V: voltage (V) I: current (A) R: resistance (Ω)
20
What can an electric current cause when it is passed through certain liquids? What is the chemical effect used in?
-An electric current can cause a chemical change when it is passed through certain liquids. -This chemical effect is used in electrolysis and extraction of metals.
20
For n resistors placed in parallel, the effective resistance R is given by
1/r = 1/r 1 + 1/r2 + 1/r3 ... then aft that the ans r/num e.g. 1/3+1/3 = 2/3 resistance = 3/2
21
the potential difference across each branch is equal to
the potential difference across the whole circuit.
21
In a parallel circuit, the sum of individual currents in each of the branches Iε = I1 + I2 + I3 + … + In
is equal to the main current.
22
What is electrolysis
Electricity can be used to break down (decompose) compounds into its elements. This process is called electrolysis.
22
An electric current has an effect on ... this effect can be seen when
magnets. This effect can be seen when an electric current flows near a compass.
22
The magnetic effect can be increased by making current flow in a coil of wire called a
solenoid.
23
The power of a circuit component is
the amount of electrical energy converted to other forms of energy per unit time by the component.
24
The SI unit of power is
watt (W)
24
What is electroplating
Many objects are coated with a metal by immersing the object in a liquid and then passing an electric current through the liquid. This method of coating objects with metals is called electroplating.
24
1 kW = 1000 W
24
The formula of energy =
energy = power X time
25
Hazards of electricity
electrical fires, electric shocks and electrocution
26
Safety features in the household electrical system
earth wire, fuse and circuit breaker
27
The ... wire (blue) is at 0 V.
neutral
28
The ... wire (yellow and green) is at 0 V. It is connected to the ... or ...
earth, ground or earth
29
The ... wire (brown) is at a high voltage. In Singapore, it is at ... V.
live, 240
30
which wire is connected to the fuse?
live wire
31
Where is the neutral wire connected to?
The bottom left of the plug
32
Where is the earth wire connected to?
The top middle part of the plug
33
electrical systems can produce effects like
heating effect, magnetic effect and chemical effect
34
What does a fuse do
The fuse makes use of the heating effect of an electric current to switch off a large current. A large current causes a short, thin wire in the fuse to heat up and melt.
34
A ... can also cut off an electric current. However, unlike a fuse, it does not need to be replaced.
circuit breaker
35
A blown fuse should be ... after an electrical fault has been rectified.
replaced
36
Why does a circuit breaker not need to be replaced?
When a damaged appliance or the damaged part of the circuit is fixed, the circuit can be switched on again using the circuit breaker.

science (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions