CAMBRIDGE LOWER SECONDARY SCIENCE 9: END-OF-UNIT TEST
Name ___________________________________
Pranavi Date _____________
Disclaimer: This test and mark scheme have been written by the authors.
End-of-unit test
Unit 3
1 a Complete the equation for density. Use the words mass and volume. [1]
density = ______________________________
mass by volume
b Look at the list of substances.
water ice wood air iron
i Circle the substance with the lowest density. [1]
ii Explain your choice of the substance with the lowest density. [1]
its particles are more far apart which means there will be less number of particles or mass
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per a particular volume
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c Water has a density of 1.0 g/cm3. A substance called LDPE has a density of 0.91 g/cm3.
Explain whether LDPE will float or sink in water. [1]
It will float as it is less dense than water.
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Cambridge Lower Secondary Science 9 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021 1
CAMBRIDGE LOWER SECONDARY SCIENCE 9: END-OF-UNIT TEST
2 Draw straight lines to match the quantity with the correct description and unit. [2]
quantity description unit
total energy of
temperature all particles in a J
substance
average energy
heat of all particles °C
in a substance
3 A hairdryer uses 1500 J of electrical energy in 1 second.
The hairdryer changes 1300 J of this to useful thermal energy in 1 second.
Calculate the quantity of energy that is wasted by the hairdryer in 1 second.
Show your working. [2]
1500-1300=200
200
______________________________ J
4 Two objects, A and B, are placed in contact with each other.
Thermal energy initially flows from A to B.
Explain the conclusion that can be made about the initial temperatures of A and B. [2]
The temperature of A is higher than B because thermal energy always flows from high energy
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to low energy
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Cambridge Lower Secondary Science 9 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021 2
