SPH3U Energy Test Review Outline
Test Date: Tuesday, May 15, 2012 (Day 1 students), Wednesday, May 16, 2011 (Day 2 students)
Format:
15 marks multiple choice, 25 marks short answer (calculate/explain)
All energy unit equations will be provided.
Topics:
Energy and Work:
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What is energy? What is work?
Forms of energy
Work done on something, work done by a force
Components of force
Work–Energy Theorem
Kinetic energy
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Gravitational potential energy
Law of Conservation of Energy
Power, Energy Efficiency
Thermal Energy, Nuclear Energy:
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What is heat? Kinetic Molecular Theory
Forms of heat transfer – conduction, convection,
radiation
Specific Heat Capacity
Law of Conservation of Heat Energy
Electricity generation and Faraday’s Law of
Induction
Energy-Mass equivalence
Nuclear structure, radioactive decay, forms of
radiation (alpha and beta particles, gamma rays)
Nuclear energy – half-life, fission, fusion, nuclear
reactors, nuclear waste management
Textbook pages and recommended textbook
questions:
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pp. 215-221, 222-224, 226-227, 228-234,
235-237
p. 221 – #3, p. 241 – #4, 12, 15, 18, 21, 22
p. 226 – #2, 3, p. 242 – #32, 33, 34
p. 228 – #1, 2, 3, p. 243 – #38, 39
p. 243 – #41, 42, 44
p. 242 - #24, 26, 28, p. 244 - #45, 46
Textbook pages and recommended study
materials:
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pp. 252-257, 260-264, 269-271, 293-295,
635-640, 641-650, 653-656, 659
p. 275 - #3, 11, 15, 23
p. 276 - #25, 29, 30, 39
p. 302 - #39, 40, p. 663 - #14, 15
p. 663 - #4, 19, 20, 22
The following formulae and constants will be provided:
W  Fd
E g  mgh
1
E k  mv 2
2
W  Ek
W
P
t
E  mc 2
EH  mtc
E H lost  E H gained
EH 1  EH 2
c = 3.0 × 108 m/s
All other necessary information will be provided: e.g. specific heat capacity of different substances,
atomic numbers and atomic masses of elements, half-lives of radioactive isotopes
Some Energy Problems:
1. Keigian and Evan push a large crate full of 150 W light bulbs (50 kg) across the floor at constant
velocity with a force of 200 N over a distance of 8 m. What is the force of friction? What is the work
done by Keigian and Evan? What is the work done on the crate? (Answers: 200 N, 1600 J, 0 J)
2. The bus (m = 1500 kg) on the band trip has broken down on the highway. Conrad, Jonah and Alec are
recruited to pull on a harness attached to the front of the bus at an angle of 25 degrees to the ground.
Together they exert a force of 1000 N on the harness and manage to move the bus 240 cm forward.
What is the component of force they are exerting in the direction of displacement? What is the work
done by the trio on the bus? Assuming the bus starts at rest, what is the change in kinetic energy of
the bus? What is the final velocity of the bus? (Answers: 906 N, 2175.1 J, 2175.1 J, 1.70 m/s)
3. An object of mass 1.0 kg is thrown upwards at 5.0 m/s from a cliff 80 m high. What is its velocity
when it is 30 m from the ground? Use conservation of energy! Another object of equal mass is
thrown downwards at 5.0 m/s. What is its velocity when it is 30 m from the ground? (Answers: 31.7
m/s, 31.7 m/s)
4. Spencer and Shirley emerge from their dungeon workshop with a 15 W lightbulb that they claim
produces 43200 J of light energy every hour. How much energy does the lightbulb actually consume
in 1 hour? What is the energy efficiency of the lightbulb? How many kilowatt-hours of energy does
the lightbulb use in 1 day? (Answers: 54,000 J, 0.80 or 80% efficiency, 0.36 kWh)
5. A 1000 kg Smart car is traveling at 100 km/h. How much kinetic energy does it have? From how high
above the ground does it need to be dropped for it to have the same amount of kinetic energy upon
hitting the ground? (Answers: 3.86 × 105 J, 39.4 m)
6. Use Kinetic Molecular Theory to explain why water in gas state is more likely to cause burns than
water in liquid state.
7. You pick up a stainless steel pot and a plastic mixing bowl that have both been stored in the same
drawer. Which one feels colder? Explain, using the concepts of heat transfer and thermal
conductivity.
8. What methods of electricity generation make use of Faraday’s Law of Induction?
9. A 100 W lightbulb is operated continuously for 1 week. How much energy does it consume?
According to Einstein’s formula, what mass of matter is this equivalent to? (Answers: 6.05 × 107 J,
6.72 × 10-10 J)
10. While moonlighting as a barista in a café on the Corso Italia, Maria pours 400 ml of coffee at 87 °C
into a 300 g pyrex mug at room temperature (25 °C). If the specific heat capacity of coffee is 4.2 ×
103 J/kg °C and that of pyrex is 7.8 × 102 J/kg °C, what is the final temperature of the mug and
coffee? Remember that 1 L of water has a mass of 1 kg, and assume that coffee has the same density
as water. (Answer: 79.4 °C0
11. A 1000 g sample of a radioactive isotope has a half-life of 23.4 minutes. How many half lives must
elapse before the sample is reduced to less than 1% of its starting mass? How much time is this? What
is the actual mass of the sample? (Answer: 7 half lives, 163.8 minutes, 7.8 g)
12. Complete the following nuclear reaction with the missing particle and determine whether it represents
alpha or beta decay or neither:
Cs 01n132
54 Xe  ____
133
55
(Answer: neither, deuterium atom ejected)
13. Complete the following nuclear reaction with the missing particle and determine whether it represents
alpha or beta decay or neither:
35
17
35
Cl 18
Ar  ____
(Answer: beta decay, electron ejected)