Cambridge Assessment International Education
Cambridge International Advanced Subsidiary and Advanced Level
* 4 6 5 1 2 0 6 2 3 5 *
PHYSICS 9702/42
Paper 4 A Level Structured Questions February/March 2019
2 hours
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams or graphs.
Do not use staples, paper clips, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
Electronic calculators may be used.
You may lose marks if you do not show your working or if you do not use appropriate units.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
This document consists of 22 printed pages and 2 blank pages.
DC (NF/SW) 162370/4
© UCLES 2019 [Turn over
, 2
Data
speed of light in free space c = 3.00 × 108 m s−1
permeability of free space μ0 = 4π × 10−7 H m−1
permittivity of free space ε0 = 8.85 × 10−12 F m−1
1
( = 8.99 × 109 m F−1)
4πε0
elementary charge e = 1.60 × 10−19 C
the Planck constant h = 6.63 × 10−34 J s
unified atomic mass unit 1 u = 1.66 × 10−27 kg
rest mass of electron me = 9.11 × 10−31 kg
rest mass of proton mp = 1.67 × 10−27 kg
molar gas constant R = 8.31 J K−1 mol−1
the Avogadro constant NA = 6.02 × 1023 mol−1
the Boltzmann constant k = 1.38 × 10−23 J K−1
gravitational constant G = 6.67 × 10−11 N m2 kg−2
acceleration of free fall g = 9.81 m s−2
© UCLES 2019 9702/42/F/M/19
, 3
Formulae
1
uniformly accelerated motion s = ut + 2 at 2
v 2 = u 2 + 2as
work done on/by a gas W = p ΔV
Gm
gravitational potential φ =−
r
hydrostatic pressure p = ρgh
1 Nm 2
pressure of an ideal gas p = 〈c 〉
3 V
simple harmonic motion a = − ω 2x
velocity of particle in s.h.m. v = v0 cos ωt
v = ± ω (x 02 - x 2)
fsv
Doppler effect fo =
v ± vs
Q
electric potential V =
4πε0r
capacitors in series 1/C = 1/C1 + 1/C2 + . . .
capacitors in parallel C = C1 + C2 + . . .
1
energy of charged capacitor W = 2 QV
electric current I = Anvq
resistors in series R = R1 + R2 + . . .
resistors in parallel 1/R = 1/R1 + 1/R2 + . . .
BI
Hall voltage VH =
ntq
alternating current/voltage x = x0 sin ω t
radioactive decay x = x0 exp(−λt )
0.693
decay constant λ =
t 1
2
© UCLES 2019 9702/42/F/M/19 [Turn over
, 4
Answer all the questions in the spaces provided.
1 (a) (i) Define gravitational potential at a point.
...........................................................................................................................................
...........................................................................................................................................
...................................................................................................................................... [2]
(ii) Use your answer in (i) to explain why the gravitational potential near an isolated mass is
always negative.
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...................................................................................................................................... [3]
(b) A spherical planet has mass 6.00 × 1024 kg and radius 6.40 × 106 m.
The planet may be assumed to be isolated in space with its mass concentrated at its centre.
A satellite of mass 340 kg is in a circular orbit about the planet at a height 9.00 × 105 m above
its surface.
For the satellite:
(i) show that its orbital speed is 7.4 × 103 m s–1
[2]
© UCLES 2019 9702/42/F/M/19
Cambridge International Advanced Subsidiary and Advanced Level
* 4 6 5 1 2 0 6 2 3 5 *
PHYSICS 9702/42
Paper 4 A Level Structured Questions February/March 2019
2 hours
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams or graphs.
Do not use staples, paper clips, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
Electronic calculators may be used.
You may lose marks if you do not show your working or if you do not use appropriate units.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
This document consists of 22 printed pages and 2 blank pages.
DC (NF/SW) 162370/4
© UCLES 2019 [Turn over
, 2
Data
speed of light in free space c = 3.00 × 108 m s−1
permeability of free space μ0 = 4π × 10−7 H m−1
permittivity of free space ε0 = 8.85 × 10−12 F m−1
1
( = 8.99 × 109 m F−1)
4πε0
elementary charge e = 1.60 × 10−19 C
the Planck constant h = 6.63 × 10−34 J s
unified atomic mass unit 1 u = 1.66 × 10−27 kg
rest mass of electron me = 9.11 × 10−31 kg
rest mass of proton mp = 1.67 × 10−27 kg
molar gas constant R = 8.31 J K−1 mol−1
the Avogadro constant NA = 6.02 × 1023 mol−1
the Boltzmann constant k = 1.38 × 10−23 J K−1
gravitational constant G = 6.67 × 10−11 N m2 kg−2
acceleration of free fall g = 9.81 m s−2
© UCLES 2019 9702/42/F/M/19
, 3
Formulae
1
uniformly accelerated motion s = ut + 2 at 2
v 2 = u 2 + 2as
work done on/by a gas W = p ΔV
Gm
gravitational potential φ =−
r
hydrostatic pressure p = ρgh
1 Nm 2
pressure of an ideal gas p = 〈c 〉
3 V
simple harmonic motion a = − ω 2x
velocity of particle in s.h.m. v = v0 cos ωt
v = ± ω (x 02 - x 2)
fsv
Doppler effect fo =
v ± vs
Q
electric potential V =
4πε0r
capacitors in series 1/C = 1/C1 + 1/C2 + . . .
capacitors in parallel C = C1 + C2 + . . .
1
energy of charged capacitor W = 2 QV
electric current I = Anvq
resistors in series R = R1 + R2 + . . .
resistors in parallel 1/R = 1/R1 + 1/R2 + . . .
BI
Hall voltage VH =
ntq
alternating current/voltage x = x0 sin ω t
radioactive decay x = x0 exp(−λt )
0.693
decay constant λ =
t 1
2
© UCLES 2019 9702/42/F/M/19 [Turn over
, 4
Answer all the questions in the spaces provided.
1 (a) (i) Define gravitational potential at a point.
...........................................................................................................................................
...........................................................................................................................................
...................................................................................................................................... [2]
(ii) Use your answer in (i) to explain why the gravitational potential near an isolated mass is
always negative.
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...................................................................................................................................... [3]
(b) A spherical planet has mass 6.00 × 1024 kg and radius 6.40 × 106 m.
The planet may be assumed to be isolated in space with its mass concentrated at its centre.
A satellite of mass 340 kg is in a circular orbit about the planet at a height 9.00 × 105 m above
its surface.
For the satellite:
(i) show that its orbital speed is 7.4 × 103 m s–1
[2]
© UCLES 2019 9702/42/F/M/19
