Physics – Marking Scheme – Year 10 – Track 3 – 2018 Page 1 of 5

DEPARTMENT FOR CURRICULUM,

RESEARCH, INNOVATION AND LIFELONG LEARNING

Directorate for Learning and Assessment Programmes

Educational Assessment Unit

Annual Examinations for Secondary Schools 2018

YEAR 10 PHYSICS MARKING SCHEME

SECTION A 40 MARKS

Question Answer Mark Additional

Guidelines

1 a longitudinal 1

1 b By means of compressions and rarefactions of air particles.

1

1 c 170 cm = 1.7 m

v = fλ → f =v

λ=

340

1.7 = 200 Hz

1

1

1 d T =1

f=

1

200= 0.005 s 1

1 e Because it is between 20 Hz to 20 000 Hz. 1 Accept ‘Because it is within the range of audible sounds’.

1 f i

1

1 f ii

1

Track 3

Page 2 of 5 Physics – Marking Scheme – Year 10 – Track 3 – 2018

2 a 0 kg m/s

2 Deduct one mark for missing or incorrect unit.

2 b 0 kg m/s because the total momentum is conserved.

1 1

2 c p = mv = 0.2 × 1.4

p = 0.28 kg m/s

1

2 d

TMB = TMA 0 = mv (air ) + mv (cart) 0 = (m × (−24)) + (0.28)

m =0.28

24 = 0.0117 kg

1 1

2 e For every action there is an equal and opposite reaction. Action and reaction act on two different bodies.

1

3 a i S1 and S2 1

3 a ii S1 , S2 , S3 and S4 1

3 a iii S1 , S2 and S3 1

3 b i No current flows. 1

3 b ii Half the current flows. 1 Accept ‘less current’.

3 b iii Double the current flows. 1 Accept ‘more current’.

3 c Variable resistor/Rheostat Voltmeter

1 1

4 a Convex/Converging Concave/Diverging

1 1

4 b

1

1

4 c Lens A/Convex lens/Converging lens 1

4 d

Lens is moved until a sharp image of the distant object forms on the wall. The distance between the lens and the image is measured with a metre ruler.

1

1

4 e Real/Diminished 1

Physics – Marking Scheme – Year 10 – Track 3 – 2018 Page 3 of 5

5 a 900 m 1

5 b 6 × 60 = 360 𝑠

Average speed = Gradient = 400

360 = 1.1 m/s

1 2

5 c She is at rest. 1

5 d Along BC. Gradient is steeper in this part of the graph.

1 1

5 e

1

SECTION B 45 MARKS

Question Answer Mark Additional Guidelines

6 a It is the rate of flow of charge. 1 Accept ‘flow of electrons per second’.

6 b i Q = It = 3 × (5 × 60) = 900 C

2

Deduct 1 mark for missing or incorrect unit.

6 b ii E = QV → V =

E

Q

=5400

900 = 6 V

2 Deduct 1 mark for missing or incorrect unit.

6 c i Ammeter: series Voltmeters: parallel

1 1

6 c ii Light Emitting Diode 1 Accept ‘LED’.

6 c iii 6 V − 1.8 V = 4.2 V 1

6 c iv

V = IR → I =V

R =

4.2

50 = 0.084 A

1

6 c v

V = IR → R =V

I =

1.8

0.084 = 21.4

2

6 c vi 0 A - 6 V 0 V

1 1 1

Accept ‘6V’.

Page 4 of 5 Physics – Marking Scheme – Year 10 – Track 3 – 2018

7

7

a

b

1

1 1 1 1

1 1

Correct path of real

rays. Correct path of virtual

rays. Labelling angles. Marking image. Drawing normal.

Labelling real depth. Labelling apparent

depth.

7 c i

2 1 1 1

Plotting correctly. Labelling axes. Correct size. Title of graph.

7 c ii Gradient =∆𝑦

∆𝑥 =

(4−2)

(3−1.5)=

2

1.5= 1.33 1

7 c iii Refractive index 1

7 d Total internal reflection occurs. 1

8 a i

3

8 a ii

1. As the electromagnet releases the sphere, the timer is activated.

2. When the sphere passes through the light gate (or hits the impact switch) the timer stops.

3. The distance fallen is measured with a metre ruler.

4. Finally the equation g =2s

t2 is used.

1

1

1

1

8 a iii g =2s

t2 = (2 × 1.5)

0.552 = 9.92 m/s2 1

0.0

1.0

2.0

3.0

4.0

5.0

0.5 1.0 1.5 2.0 2.5 3.0 3.5

Re

al d

ep

th (

m)

Apparent depth (m)

A graph of real depth (m) vs apparent depth (m)

i

light rays

r

I real depth

apparent depth

iron sphere

Physics – Marking Scheme – Year 10 – Track 3 – 2018 Page 5 of 5

8 b i

Air resistance increases with increasing speed. Eventually it becomes equal to the weight of the person.

1

1

8 b ii Change in momentum = mv − mu

= (118 × 373) − (118 × 0)= 44 014 kg m/s

1

1

Deduct 1 mark for missing or incorrect unit.

8 b ii F =

change in momentum

time

F = 44 014

42 = 1048 N

1

1

8 b ii 1180 – 1048 = 132 N

1

Please Note: When marking questions that involve calculations, apply the ‘follow through’

rule. This means that if a student gives a wrong value for part (a) of a question and then uses

the value of (a) in the subsequent calculations, marks should be deducted for part (a) only. The

subsequent parts should be given full marks if these are correct.