P510/1
Physics
Paper 1
Mocks 2013
2½ Hours
TURKISH LIGHT ACADEMY
PHYSICS MOCK EXAMINATIONS – 2013
Uganda Advanced Certificate of Education
PHYSICS
Paper 1
2 hours 30 minutes
INSTRUCTIONS TO CANDIDATES:
Answer five questions, including at least one, but not more than two from each of
the sections A, B and C.
Non – programmable scientific calculators may be used.
Assume where necessary.
Acceleration due to gravity
g
Avogadro’s constant
Electron charge
e
Election mass
Radius of Earth
Radius of the sun
Radius of orbit of the Earth
Speed of light in vacuum
Wien’s constant
Specific heat capacity water
Planck’s constant h
Specific latent heat of steam
Stefan’s – Boltzmann’s constant, 𝝈
Thermal conductivity of Iron
Universal gravitational constant, G
Avogadro’s number, NA
Density of water
Density of mercury
Gas constant, R
Young’s modulus for Copper
Young’s modulus for steel
= 9.8ms-2
= 6.02 x 1023 mol-1
= 1.6 x 10-19C
= 9.1 x 10-31kg
= 6.4 x 106m
= 7.0 x 108m
= 1.5 x 1011m
= 3.0 x 108ms-1
= 2.9 x 10-3mK
= 4.2 x 103Jkg-1K-1
= 6.63 x 10-34Js
= 2.26 x 106Jkg-1
= 5.67 x 10-8Wm-2K-4
= 80Wm-1K-1
= 6.67 x 10-11Nm2kg-2
= 6.02 x 1023 mol-1
= 1,000kg m-3
= 13,600kg m-3
= 8.31J mol-1K-1
= 1.2 x 1011 Pa
= 2.0 x 1011 Pa
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SECTION A
1(a) Distinguish between conservative and non-conservative forces and give an example of each.
(03 marks)
(b) A ball is thrown vertically upwards from the top of a building to 10.5m tall. The ball takes
9.0 seconds to reach its maximum height.
(i) Sketch a graph of displacement against time for the motion of the ball.
(ii) State the energy changes that take place as the ball moves upwards.
(02 marks)
(02 marks)
(iii) Find the time taken by the ball to hit the ground below from the time it is thrown. (03 marks)
(c)
(i) State Newton’s law of gravitation.
(01 mark)
(ii) A body of mass m kg is at a height h metres above the earth’s surface. Show that the
mechanical energy of the body is given by
−𝐺𝑀𝑚
2(ℎ+𝑅𝑒 )
where G is gravitational constant, M is
mass of the earth and Re is the earth’s radius.
(05 marks)
(iii) If the acceleration due to gravity at height h in (c)(ii) above is a ninth of the acceleration due
to gravity on the earth’s surface, find the value of h.
2(a)
(04 marks)
(i) Define surface tension.
(01 mark)
(ii) Give the molecular explanation of surface tension.
(b)
(03 marks)
(i) Derive an expression for the pressure difference inside and outside a soap bubble of
radius r and surface tension 𝛾.
(03 marks)
(ii) Two soap bubbles of radii 2.2cm and 3.0cm respectively coalesce under isothermal
conditions. If the surface tension of the soap solution is 2.6 x 10-2Nm-1. Calculate the
excess pressure inside the resulting soap bubble.
(c)
(i) State Bernoulli’s principle.
(04 marks)
(01 mark)
(ii) Explain why an aeroplane has to bank its wings in order to make a curved path in
space.
(04 marks)
(iii) Water flows through a horizontal pipe of varying cross-section. If pressure of water is
8.0cm of mercury where the velocity of flow is 0.3m-1, what is the pressure at another point
where the velocity of flow is 0.8ms-1 . (04 marks)
2
3.
(a)
Distinguish between elastic and perfectly inelastic collisions.
(02 marks)
(b)
A bullet of mass 0.012kg and horizontal speed 70m-1 strikes a block of wood of
mass 0.4kg and instantly comes to rest with respect to the block. The block is
suspended from the ceiling by means of a thin string.
(c)
(i) Calculate the height to which the block rises.
(04 marks)
(ii) Estimate the amount of heat produced in the block.
(02 marks)
(i) Define the following terms, Young’s modulus and work hardening as used in
relation to properties of matter.
(02 marks)
(ii) Show that the energy stored per unit volume of a stretched wire is given by
1
2
(d)
𝐸(𝑠𝑡𝑟𝑎𝑖𝑛)2 E is Young’s modulus.
(04 marks)
A copper wire and steel wire of the same diameter and of length 1.0m and 2.0m
respectively are connected end to end. A force is applied which stretches their
combined length by 1.0cm. Find:
4.
(a)
(i) The extension in each wire.
(04 marks)
(ii) The stress in the composite wire.
(02 marks)
(i) State Archimedes’ Principle
(01 mark)
(ii) A piece of brass (an alloy of copper and zinc) weighs 12.9g in air. When fully
immersed in water it weighs 11.3g. What is the mass of copper contained in the
alloy given that the relative densities of copper and zinc are 8.9 and 7.1
respectively?
(b)
(c)
(05 marks)
(i) State the characteristics of simple Harmonic motion.
(02 marks)
(ii) Distinguish between damped and forced oscillations.
(02 marks)
A body executing Simple Harmonic Motion has a velocity of 0.03ms-1, when its
displacement is 0.04m and a velocity of 0.04ms-1 when its displacement is 0.03m.
(i) the amplitude and
(04 marks)
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(ii) the period of oscillation
(03 marks)
(iii) if the mass of body is 50g, calculate the total energy of oscillation. (03 marks)
SECTION B
5.
(a)
(i) Define specific latent heat of vaporization.
(01 marks)
(ii) With the aid of a well labeled diagram, describe the accurate methods of
determining the specific latent heat of vaporization water.
(b)
(06 marks)
A warm water tap and a cold water tap are opened at the same time into a bath
table. Water from the warm water tap flows out at a rate of 3.0kg min-1 at a
temperature of 60oC, while cold water flows out at a rate of 4.0kg,min-1. When
the taps have been opened for 50.0 seconds, the temperature of the water in the
tab is found to be 32oC. If the water in the tab loses heat at an average rate of
100W, find,
(c)
(i) the mass of water in the tab after 50.0 seconds.
(02 marks)
(ii) the temperature of the water flowing out of the cold water tap.
(04 marks)
(i) Define thermal conductivity of a material.
(01 mark)
(ii) A house has an iron roof of area 5.0m2. The temperature on top of the roof is
30oC while that inside the room is 20oC. If the iron sheets are 1.0mm thick, find
the percentage decrease in the rate of heat flow into the room.
(04 marks)
(iii) If a ceiling material of thermal conductivity 0.6 Wm-1K-1 and thickness
1.0mm.
6(a)
1
(i) State the assumptions made in the derivation of the gas equation P = 3 ̅̅̅̅̅
𝜌𝑐 2 (02 marks)
(ii) state Dalton’s law of partial pressures.
1
(01 mark)
(iii) Use the expression P = 3 ̅̅̅̅̅
𝜌𝑐 2 to deduce Dalton’s law stated in (ii) above. (03 marks)
(b)
Explain
4
(i) what happens to the pressure of a fixed mass of a gas in a sealed container
when the temperature of that gas is raised.
(04 marks)
(ii) Why water on top of a high mountain boils at a lower temperature than that at
the bottom of the mountain.
(c)
(04 marks)
Two hollow sphere A and B of volume 500cm3 and 250cm3 respectively at
connected by a narrow tube fitted with a tap. Initially the tap is closed and A is
filled with an ideal gas at 10oC at a pressure of 3.0 x 105Pa and B is filled with an
ideal gas at 100oC at a pressure of 1.0 x 105 Pa. Calculate:
(i) the equilibrium pressure when the tap is opened.
7.
(a)
(b)
(03 marks)
(ii) the resulting temperature when the tap is opened.
(03 marks)
(i) Define a thermometric property.
(01 mark)
(ii) State any four thermometric properties.
(02 marks)
(i) With the use of a well labeled diagram explain how a constant volume gas
thermometer is used to measure the absolute temperature of a substance.(5 marks)
(ii) State two advantages and two disadvantages of a constant volume gas
thermometer.
(c)
(02 marks)
(i) The electrical resistance in ohms of a certain thermometer varies with
temperature T, according to the equation R = R0[1 + 4 x 10-3(T-T0)]. The
resistance is 112Ω at 600K.
What is the temperature when the resistance is 120Ω?
(06 marks)
(ii) Explain why on a winter night one would feel warmer when clouds cover the
sky than when the sky is clear.
(04 marks)
SECTION C
8.
(a)
(i) State one biological and one industrial use of x-rays.
(02 marks)
(ii) Draw a well labeled diagram of a modern x-ray tube.
(02 marks)
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(b)
The tube voltage of an x-ray tube is 4,000V and a tube current of 35.0mA flows
across the tube.
(i) How many electrons strike the target per second?
(02 marks)
(ii) Calculate the energy delivered to the target every second.
(02 marks)
(iii) If the filament is 60.0cm from the metal target, find the number of electrons
within a 1.0cm length between the filament and the target.
(c)(i) Define Avogradro’s constant and Faraday constant.
(ii)
(04 marks)
(02 marks)
1.8 x 1024 singly charged ions are to be liberated in an electrolyte when a current of 8.0A
flows through it. Calculate the time in hours for which the current must flow through the
electrolyte.
(03 marks)
(d)
Explain how Milikan concluded that charge was quantized.
(03 marks)
9.
(a)
Define Half-like and decay constant.
(02 marks)
(b)
A radioactive element X decays by emitting an alpha particle and a beta particle
92
to form element 45𝑌. Find:
(i) the number of protons and the number of neutrons in an atom of element X.
(02 marks)
(ii) the activity of a 7.0g sample of X, if the half-life of X is 3.4 days.
(c)
(d)
(04 marks)
Using a well labeled diagram, explain how a Geiger Muller tube is used to detect
radiation from a radioactive substance.
(05 marks)
(i) State the laws of photoelectric emission.
(04 marks)
(ii) When electromagnetic radiation of wavelength 4.58 c 10-7m is incident on a
metal surface, electrons of maximum energy 2.0eV are emitted. Find the work
10.
(a)
function of the metal surface.
(03 marks)
(i) What are cathode rays?
(01 mark)
(ii) State any four properties of cathode rays.
(02 mark)
6
(b)
Describe an experiment to measure specific charge of an electron.
(6 marks)
(c)
Electrons of energy 2.0KeV enter midway between two parallel plates, in a direction
parallel to the plates. The plates are 5.0cm long and 1.5cm apart. They are maintained at a
potential difference of 240V.
(i) Find the speed of the electrons as they emerge from the region between the plates.
(04 marks)
(ii) Calculate the deflection of the electron beam on a screen placed 30cm beyond the plates.
(04 marks)
(d)
Draw a labeled diagram showing the essential features of a cathode ray oscilloscope.
(03 marks)
END
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