2012 Annual Examinations
Subject: Physics Time: 2 Hours
Teacher’s Name: Mr GJ Zahra, Mr M Mallia No. of Pages: 11
Name & surname: __________________________ Class: Year 9._____
This paper consists of ten questions. Each question carries a total of ten marks.
Answer all questions in the space provided.
Mark allocations are shown in brackets next to each question.
Write down your Name, Surname and Class on all your answer sheets.
You are requested to show all working and write down the units where necessary.
You are reminded of the necessity of good English and orderly presentation of your work.
In calculations, you are advised to show ALL the steps in your working.
Where necessary, take g, acceleration due to gravity, to be 10 m/s2.Below is a set of formulae that you might find useful during the examination:
Density
Pressure
Energy & Work
Force
Heat
Item Lab
Report 1 2 3 4 5 6 7 8 9 10 Total Total
Max.
Mark 15 10 10 10 10 10 10 10 10 10 10 115 %
1. Peter investigates the densities of three different materials: copper, aluminium and
modelling clay (plasticine).
a. The copper block is 5cm wide, 5cm thick and 4cm high. Its mass is 890g.
Calculate the density of copper in g/cm3.
____________________________________________________________
__________________________________________________________ (2)
b. Peter finds that an aluminium block of the same volume has a density of 2.7
g/cm3. Give one reason why aluminium and copper have different densities. ____________________________________________________________
__________________________________________________________ (1)
c. Peter observes that aluminium sinks when placed in water but floats on liquid
mercury. Explain these observations.
____________________________________________________________
__________________________________________________________ (2)
d. Peter tries to find the volume of modelling clay using the following apparatus in
order to find its density
i. Describe how the volume of modelling clay is measured
_______________________________________________________
_______________________________________________________
_____________________________________________________ (3)
ii. Give two precautions Peter needs to take to measure the volume of
modelling clay accurately
_______________________________________________________
2. The diagram shows an aluminium pan being heated on an electric burner. Food is being
cooked in boiling oil in the pan.
a. Name the process by which heat is transferred through the saucepan
__________________________________________________________ (1)
b. The figures show three different ways in which particles in a substance may be
arranged.
Indicate which figure best represents the arrangement of the particles:
i. In the aluminium pan
_____________________________________________________ (1)
ii. Of the gas above the boiling oil
_____________________________________________________ (1)
c. Give two reasons why the pan is made of aluminium
____________________________________________________________
__________________________________________________________ (2)
d. Suggest a suitable material for the pan handle
__________________________________________________________ (1)
e. Calculate the heat energy needed to raise the temperature of the 300g pan from
25°C to 100°C if the specific heat capacity of aluminium is 900 J/kg°C.
____________________________________________________________
__________________________________________________________ (2)
f. Why are solar panels and the radiator at the back of a refrigerator both painted
black?
____________________________________________________________
3. The diagram below shows the beads on a Newton’s Cradle
a. What is the main type of energy that the beads have at points
i. A: ___________________________________________________ (1)
ii. B: ___________________________________________________ (1)
b. The mass of each bead is 0.05kg. Calculate its potential energy at point A.
____________________________________________________________
__________________________________________________________ (2)
c. What is the kinetic energy of the bead at point B?
__________________________________________________________ (1)
d. Calculate the velocity of the bead at point B.
____________________________________________________________
__________________________________________________________ (2)
e. When the bead hits the other beads at B, a bead from the other side moves up
and reaches a height of 4.7cm.
i. State the principle of conservation of energy
_______________________________________________________
_____________________________________________________ (2)
ii. Why does the bead not reach a height of 5cm in practice?
4. Monica drops a ball from a height above the ground.
a. On the diagram below draw and name the forces acting on the ball as it is
accelerating downward (3)
a. If the ball has a mass of 0.35 kg, calculate the downward force acting on the ball.
____________________________________________________________
__________________________________________________________ (2)
b. Using your answer in (a), calculate the resultant force acting on the ball if the
upward force is 1.5N
__________________________________________________________ (1)
c. Monica then drops the same ball along a rough slope. Explain in terms of forces
why the ball takes more time to reach the ground.
____________________________________________________________
__________________________________________________________ (2)
d. Explain what is meant by the term centre of gravity.
____________________________________________________________
5. A crane transports a 500kg mass from ground level up to an 80m sky scraper. The work
done by the crane in lifting the load is measured and calculated every 20m
Work Done W (kJ) 0 100 200 300 400
Height h (m) 0 20 40 60 80
a. Plot a graph of the Work Done W (kJ) on the y-axis against Height h (m) on the x-axis
(4)
b. Use the graph to obtain the value of the work done by the crane in lifting the mass to a height of 70m. Mark this point clearly on your graph with an ‘X’.
____________________________________________________________
__________________________________________________________ (2)
c. Calculate the slope (gradient) of the graph, giving your answer in J/m.
____________________________________________________________
__________________________________________________________ (2)
d. Using the value obtained in (c), or otherwise, calculate a value for the gravitational
acceleration in the formula:
____________________________________________________________
6. This question is about pressure and its uses.
a. John traps some air inside a syringe. He closes the open
end with his thumb and pushes in the piston. State what happens to the air’s:
i. Volume: _____________________________________________
ii. Mass: _______________________________________________
iii. Density: _____________________________________________
iv. Pressure: ____________________________________________ (4)
b. Waste paper is sent to a recycling plant. The diagram shows a hydraulic press
used to crush waste paper.
i. The piston Y has an area of 0.5 m2. Calculate the pressure exerted when the handle is pushed in with a force of 50N.
_______________________________________________________
_____________________________________________________ (2)
ii. What is the value of the pressure at X?
_____________________________________________________ (1)
iii. Work out the value of the force with which the piston X crushes the paper if
the area of piston X is 2.0 m2.
_______________________________________________________
_____________________________________________________ (2)
iv. Give one reason why oil is used instead of water as a hydraulic fluid.
7. This question is about energy sources
a. State the difference between renewable and non-renewable sources of energy.
____________________________________________________________
__________________________________________________________ (2)
b. Classify the following energy sources as renewable or non-renewable
Solar energy Fossil fuels Biomass fuels Nuclear energy
Renewable Non-Renewable
c. Select one energy source from the ones listed above and give one advantage and
one disadvantage of using such source in Malta
____________________________________________________________
__________________________________________________________ (2) d. At the Power Station in M’Xlokk, oil is burnt to turn the turbines in order to
generate electricity. Fill in the energy conversions in the flow chart drawn below
8. The Earth is one of the eight planets in orbit around the sun in what is known as the solar
system
a. Which planet in the solar system has the shortest year? Explain.
____________________________________________________________
__________________________________________________________ (2)
b. Give one reason why Pluto was officially removed from being one of the planets of
our solar system
__________________________________________________________ (1)
c. In 1609, Galileo Galilei, an Italian scientist, performed the first observation of the
planets using a telescope of only 4 cm in diameter. He observed the distant planet
Jupiter and discovered four faint dots around this planet.
i. Suggest what the four faint dots around Jupiter might be.
_____________________________________________________ (1) ii. Name the force that keeps these ‘dots’ in orbit around Jupiter.
_____________________________________________________ (1)
iii. Is the average surface temperature on Jupiter colder or warmer than that
on Earth? Give one reason for your answer.
_______________________________________________________
_____________________________________________________ (2)
d. The Ursa Major galaxy is 1 x 109 light years away from us. If light travels with a speed of 3 x 108 m/s, calculate the distance of the galaxy from Earth. Give your answer in standard form.
____________________________________________________________
____________________________________________________________
____________________________________________________________
9. Isaac attaches a weight of 2N to a spring.
a. What can be attached to the spring to make readings of length easier
to take?
_______________________________________________ (1)
b. Describe how Isaac finds a value for the extension produced on the
spring.
____________________________________________________________
____________________________________________________________
__________________________________________________________ (3)
c. Isaac attaches more masses to the spring and measures the extension for each
mass added. Sketch the shape of the graph he obtains when the force applied is
plotted against the extension. Assume the elastic limit is not exceeded. (2)
d. On the same axis used in (c), sketch the graph obtained if Isaac uses a stiffer
spring. Label this graph S. (1)
e. Explain why the shapes of the graphs are different.
____________________________________________________________
__________________________________________________________ (2)
f. What happens to the graph in (c) if the elastic limit is exceeded?
10. The diagram below shows a uniform trapdoor of mass 2kg held horizontal by a vertical
copper wire fixed to a point as shown
a. What is the weight of the trapdoor?
____________________________________________________________
__________________________________________________________ (2)
b. On the diagram,
i. Draw the weight acting on the trapdoor (2)
ii. Draw the tension force acting on the copper wire (1)
c. Taking moments about the pivot, calculate
i. The clockwise moment
_______________________________________________________
_____________________________________________________ (2)
ii. The anticlockwise moment
_____________________________________________________ (1)
iii. The size of the force acting on the copper wire
_______________________________________________________
_____________________________________________________ (2)
