National 5 Revision Questions

MATHEMATICS PACKAGE

List the method (or steps) that you should follow in order to calculate a physical quantity, for example speed, current, power.

A box has a volume of 25 m3 . Its breadth is 2.5 m and its height is 0.5 m, what is its length?

Put the following formula into a magic triangle and use it to find out how you would calculate ‘g’

Ep = m g h

How do you find the circumference of a circle?

How would you calculate the number of seconds in a year?

How would you calculate how FAR light travelled in ONE YEAR?

List 4 important points to bear in mind when drawing graphs?

If the cost of 25 cm3 of a liquid costs 65p, how much would 70 cm3 cost?

Round the following number to 2 decimal places:

7.8934562

Round the number above to 2 significant figures.

Write the following number in standard index form:

28000000

Write the following number in scientific notation:

0.000465

How would you put the numbers in questions 11 & 12 into your calculator?

Draw a graph of speed against time. Show an object that speeds up from 0 m/s at time 0 seconds to 2 m/s after 15 seconds. The increase should be steady and so a straight line.

The area under a speed-time graph, (like the one you have drawn in question 12) tells us the distance you have travelled during the journey shown on the graph. Find the area under the graph that you have drawn in question 12 and so find the distance travelled during the journey.

ELECTRICITY & ENERGY

1.	What is the colour of the insulation on the wire which should be connected to the live pin of a mains plug.

Blue

Brown

Black

Blue and Yellow

Green and Yellow

2.	The circuit diagram below shows five components, labelled A, B, C, D, and E, connected to a d.c. supply.

Which component symbol represents a variable resistor?

3.	Which of the following is the unit of electrical energy?

Ampere

Volt

Coulomb

Watt

Joule

4.	Which of the following is the circuit symbol for a fuse?

5.	Which of the following shows the correct circuit for measuring the current in the lamp?

6.	A lamp is connected in series with a resistor to a 12 volt supply as shown. The current in the lamp is 02 ampere and the voltage across it is 35 volts.	.

What is the current in the resistor?

What is the voltage across the resistor?

7.	(a)	The mains supply and the car battery are two common sources of electricity. The table below lists the voltage, frequency and type of current for one or other of these sources

Supply	Voltage	Frequency	Type of current
Mains supply	a.c.
Car battery	12 volts	0

Copy and complete the table to provide the missing details.

(b)	A 12 volts car battery supplies the electrical energy for a car’s 60 watt hi-fi system.

(i)	What is the maximum electrical energy transformed each second in the hi-fi system?

(ii)	Calculate the current drawn from the battery when the system is operating at full volume.

(iii)	The interior lamp in the car draws a current of 05 ampere when it is switched on.

Calculate the resistance of the lamp.

8.	The diagrams below show the rating plates attached to a musical keyboard and to a television.

(a)	Which appliance should be connected to an alternating current supply?

(b)	Explain, in terms of current, the difference between direct current and alternating current.

(c)	Use the information on the rating plate to calculated the current to the keyboard.

9.	(a)	How can you show, without tampering with the wiring, whether house lights are connected in series or parallel?

(b)	A “two way” switch circuit is shown below.

(i)	Copy and complete the table below to show the state of the lamp for the different positions of the two switches.

switch 1	switch 2	lamp (on/off)
a	a	on
a	b
b	b
b	a

(ii)	If the lamp is lit, as in the diagram, in what two ways could it be turned off again?

(iii)	This circuit is used to control the lamp on a stairway. Switch 1 is at the bottom of the stairs and switch 2 is at the top. Explain the advantage of this over having only one switch.

(b) The table below shows some information on four metals P, Q, R and S.

Metal	Melting point (degrees Celsius)	Resistance
P	420	high
Q	3400	high
R	660	low
S	2500	low

(i)	From the information given in the passage about lamps and the table on metals, select the most suitable metal for the filament of a lamp.

(ii)	Explain your choice of metal.

12.	The diagram below shows the connections between a 12 volt car battery and a rear window heater.

When the switch is closed there is a current of 10 amperes in the circuit.

(a)	Calculate the power of the heater.

(b)	What is the resistance of the heater?

(c)	The heater element becomes hot but the connecting wires remain cold.

Copy and complete the following statement by putting the phrase less than or the same as or greater than in the space.

The resistance of the connecting wires is .......................................... the resistance of the heater element.

3.	A tail and brake lamp on a car has two filaments in the same glass bulb as shown in figure 1. One filament has a resistance of 7 Ω and the other a resistance of 28 Ω. Figure 2 shows the circuit containing the two filaments.

What is the resistance of the two filaments when connected in parallel by closing switches X and Y?

(b)	For safety reasons, the brake light has a higher power than the tail light. Explain which filament acts as the brake light.

In the circuit shown below, a voltmeter is connected across an unknown component X. When switch S is closed, the reading on the voltmeter rises very slowly to a maximum value.
Which of the following components is X?

Capacitor

Resistor

Bulb

Diode

LED

In the circuit below, the resistors P, Q, R and S have the same value.
In which of the resistors is the current the same?

Q and S only

P, Q and S only

P, Q, R and S

P and R only

R and Q only

Which of the following is the circuit symbol for a thermistor?

Which of the following is an output device?

LDR

LED

Microphone

Solar cell

Thermistor

The purpose of the amplifier in a personal stereo is to

convert an analogue signal to a digital signal

transform an electrical signal to a sound signal

transform a sound signal to an electrical signal

increase the frequency of an electrical signal

increase the amplitude of an electrical signal.

Three members of a school electronics club are planning their next projects. One project is to build a light meter. A second project is to build a circuit which will control the opening and closing of curtains from a distance. The third project is to build a sound operated baby alarm.
The members use a catalogue to select components for their projects. The catalogue has the following list giving details of input and output devices.

Which of the devices listed in the catalogue is a suitable input device for the baby alarm?

Name two devices in the list which are output devices.

Name, from the list, a suitable output device for the curtain control circuit.

State the useful energy change which takes place in the solar cell.

The light meter project involves the use of the light dependent resistor (LDR) in a circuit as shown below.
Calculate the current in the circuit when the LDR is exposed to light.

A thermocouple is used as a temperature sensor in a furnace. The thermocouple is attached to a chart recorder that records the voltage generated by the thermocouple over a period of time.

State the energy transfer that takes place in the thermocouple.

Is the output of the chart recorder analogue, binary or digital.

The thermocouple is now connected to a circuit that has a digital display
The resistance of the circuit is 500 ohms. At a particular temperature, the thermocouple generates a voltage of 0.8 volt.
Calculate the current in the thermocouple circuit.

Radioactivity Questions

In which unit is the activity of a radioactive source measured?

A.	becquerel

B.	hertz

C.	joule

D.	sievert

E.	watt

2.	Which of the following can be used to detect X-rays?

A.	thermistor

B.	optical fibre

C.	photographic film

D.	stethoscope

E.	bimetallic strip

3.	Atoms contain three particles - electrons, protons and neutrons.

Which entry in the table correctly describes the position of these particles?

Inside the nucleus	Outside the nucleus
A B C D E	electrons and protons electrons and neutrons electrons protons protons and neutrons	neutrons protons protons and neutrons electrons and neutrons electrons

4.	The degree celsius is a unit of

A	heat

B	temperature

C	energy

D	frequency

E	weather

Doctors carry out some internal examinations without having to use surgery. One piece of apparatus involves the use of ultrasound waves.

Give one example of an internal examination using ultrasound.

A sample of air containing a radioactive gas was collected from a house in Cornwall. The sample and a detector were put into a sealed lead container. A cutaway section of the container is shown below. The count rate for the sample was found at various times.

a)

i)	Why were the sample and detector enclosed in a thick lead container?

ii)	The measurements of count rate for the sample as time passed were as follows:

Time in hours	0	30	60	90	120	150	180
Count rate in counts per minute	42.0	33.5	26.7	21.3	17.0	13.6	10.8

Use these figures to give an estimate of the half-life of the radioactive gas.

b)	Such gas samples from Cornwall emit radiation which gives a high density of ionisation compared with the other two types of radiation emitted by natural substances.

i)	What does the term ionisation mean?

ii)	What kind of radiation is the sample emitting?

iii)	Explain why this gas is dangerous if it is breathed in.

c)	Using the data sheet, on page two, state which radioactive element is present in the sample.

The diagram shows a ray of light striking a plane mirror. Which path shows the reflected ray?

The diagrams below show the forces acting on identical toy cars. Which car is moving at a steady speed?

Two radiations, X and Y, are emitted from a radioactive source. The diagram below shows how far they will travel when sheets of paper, aluminium, and lead are placed in front of the source.

Which of the following correctly names both radiations X and Y?

Radiation X	Radiation Y
A	alpha	beta
B	beta	gamma
C	gamma	alpha
D	alpha	gamma
E	beta	beta

A V 12 V + _ polystyrene cup heater water

Which two additional pieces of apparatus are required to make measurements during this experiment?	2

Using the above arrangement, the immersion heater is placed in 0.20 kg of water and switched on for a time of 280 s. The temperature of the water is raised from 20ºC to 35ºC. The readings on the ammeter and voltmeter are 4.0 A and 12 V respectively. Assuming all of the electrical energy supplied to the heater is transferred into heat in the water; calculate the specific heat capacity of the water.

3

Suggest a change to the set up which would reduce the heat lost from the water during the experiment.

1

What effect would this change have on the calculated value for the specific heat capacity of the water?	1

(7)

ELECTRICITY & ELECTRONICS

A car headlamp is operating at its rated values of 12 V and 48 W.

Which of the following statements is/are correct?

I	The lamp uses energy at the rate of 48 joules per second.

II	The current through the lamp is 4 amperes.

III	12 coulombs of charge flow through the lamp every second.

I only

II only

I and II only

II and III only

I, II and III.

Which of the following is the unit of gravitational field strength?

kg m/s

N m

N m/s

kg m/s2

N/kg

The circuit symbol for a fuse is

A circuit is set up containing several LEDs. Which of the LEDs will light in this circuit?

Which of the following waves is a longitudinal wave?

Microwaves

Radio waves

Sound waves

Light waves

Water waves

A thunderstorm takes place and an observer hears the thunder 5 s after seeing the flash of lightning.

The distance between the observer and the lightning in metres is approximately

An atom of helium consists of electrons, neutrons and protons.

The nucleus contains

electrons only

neutrons and electrons

protons and electrons

protons and neutrons

protons, neutrons and electrons.

Why is alpha radiation the most harmful to the body?

It produces the greatest ionisation density.

It is the most penetrating.

It has the slowest moving particles.

It is produced by unstable nuclei.

It produces the highest-energy electrons.

A radioactive substance is to be injected into a patient so that blood flow can be monitored.

A number of different substances which emit either or radiation are available.

The substances have different half-lives.

Which substance, A, B, C, D or E is the most suitable?

Substance	Radiation emitted	Half-life
A	2 days
B	2 years
C	2 seconds
D	2 days
E	2 years

Which of the following gives the correct units for the measurement of radiation?

Activity	Equivalent Dose	Radiation weighting factor
A	becquerels	sieverts	no unit
B	sieverts	grays	no unit
C	joules	grays	no unit
D	becquerels	grays	Sieverts
E	becquerels	sieverts	Joules

Which of the following correctly describes an alpha particle?

Weakly ionises, blocked by paper and has a positive charge

Weakly ionises, requires thick lead to block and has a positive charge

Weakly ionises, blocked by paper and has no charge

Strongly ionises, blocked by paper and has a positive charge

Strongly ionises, cannot be blocked by paper and has a negative charge