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August 2010Class C 1

UNIQUE SCIENCE ACADEMY

This document consists of printed pages.

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General Certificate of Education Ordinary Level

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 a soft pencil for any diagrams, graphs or rough working.Do not use staples, paper clips, highlighters, glue or correction fluid.

Section AAnswer all questions.Write your answers in the spaces provided on the Question Paper.

Section BAnswer any two questions.Write your answers on the lined pages provided and, if necessary, continue on the separate answer paper provided.

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.

PHYSICS

5054/02

Paper 2 Theory

1 hour 45 minutesCandidates answer on the Question Paper.

Additional Materials: Answer Booklet/Paper.

For Examiner’s Use

Section A

Total

If you have been given a label, look at thedetails. If any details are incorrect ormissing, please fill in your correct detailsin the space given at the top of this page.

Stick your personal label here, ifprovided.

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Section A

Answer all the questions in this section.

1 A diver holds his breath and dives into the sea from a boat to a depth of 25.0 m. The atmospheric pressure is 1.05 × 105 Pa.

(a) (i) Explain why the pressure at this depth is greater than the atmospheric pressure.

..................................................................................................................................

.............................................................................................................................. [1]

(ii) Other than the depth and the atmospheric pressure, state one quantity that affects the pressure in a liquid.

..................................................................................................................................

.............................................................................................................................. [1]

(b) (i) The pressure due to 25.0 m of sea-water is 2.55 × 105 Pa. Calculate the total pressure at this depth.

pressure = .................................................. [1]

(ii) As the diver holds his breath and descends to a depth of 25.0 m, the greater pressure causes the volume of the air trapped in his lungs to change.

When he is on the boat, the total volume of the air in his lungs is 6000 cm3. Calculate the volume of this air at a depth of 25.0 m.

volume = .................................................. [2]

Fig. 2.1

Fig. 2.1 shows how the height 2

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A piece of paper falls from 4.0 m above the ground. h above the ground varies with the time t.

0 0.5 1.51.0t / s

h /m

2.00

2.0

1.0

3.0

4.0

(a) State what happens to the speed of the paper as it falls.

..........................................................................................................................................

..........................................................................................................................................

..................................................................................................................................... [2]

(b) Calculate the speed of the paper at time t = 1.5 s.

speed = ………………………………… [2]

(c) As the paper falls, energy changes from one form to another. State the main energy change between t = 1.0 s and t = 2.0 s.

..........................................................................................................................................

..........................................................................................................................................

..................................................................................................................................... [2]

mass = ............................................. g [2]

Fig. 4.1

Fig. 4.1 shows a bottle opener.4

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The sides of a cube are 3.00 cm long. The cube is made from a metal of density 7.50 g / cm3.

(a) State the name of the measuring instrument that could be used to measure the length of the cube to the precision indicated.

.................................................................................................................................... [1]

(b) Calculate the mass of the cube.

11cm

F

effort = 30N

1.5cmpivot P

bottlecap

bottle opener

A force of 30 N is applied at a distance of 11 cm from the pivot P. The force F on the bottle cap is 1.5 cm from the pivot P.

Calculate the force F on the edge of the cap.

force = ............................................ N [3]

Fig. 5.1

bent, as illustrated in Fig. 5.1.5

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As a pole vaulter runs towards the jump, his pole is straight. When he is jumping, the pole is

pole

(a) Which form of energy of the athlete increases as he accelerates towards the jump?

.................................................................................................................................... [1]

(b) Which form of energy is stored in the pole because it is bent?

.................................................................................................................................... [1]

(c) Which form of energy of the athlete increases because he is rising towards the bar?

.................................................................................................................................... [1]

(d) Which two quantities need to be known in order to calculate how much work is done lifting the athlete up from the ground to the bar?

............................................................. and .............................................................. [1]

Fig. 6.1

Fig. 6.1 shows a lever that is used to lift a heavy object.6

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90cm

25N5.0cm

heavy object

F

P

A force of 25 N is applied at a distance of 90 cm from the pivot P. The load F on the lever is 5.0 cm from pivot P. The directions of the 25 N force and of the load F are both at right-angles to the lever.

(a) Calculate the load F on the lever.

State the unit.

force = ................................................ [3]

(b) The point of application of the force of 25 N is moved through a distance of 0.08 m in the direction of the 25 N force. Calculate the work done on the lever.

State the unit.

work done = ................................................ [3]

[2]

[2]

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The water level in a measuring cylinder rises from the 40 cm3 mark to the 65 cm3 mark whena stone of mass 125 g is totally immersed in the water.

Calculate the density of the stone.

An object of mass 0.4 kg is set into motion so that it slides up a friction-free slope with aninitial speed of 6 m / s. The object comes to rest after 2 s.

Calculate, for this object,

(a) its initial kinetic energy,

(b) the potential energy it gains in moving up the slope,

[1]

(c) its acceleration.

[2]

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Fig.9.1

Fig.9.1 shows a car travelling at 30 m/s on a level road. At this speed the car has to9

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overcome a total force of 600 N opposing the car.

(a) (i) Calculate the distance travelled by the car in 10 s.

distance = ......................................

(ii) State the value of the driving force produced by the engine for a steady speed of30 m/s.

...................................................................................................................................[2]

(b) Explain why the car slows down when it climbs a hill, even though the driving force isunchanged.

..........................................................................................................................................

..........................................................................................................................................

......................................................................................................................................[1]

(c) While on the level road and travelling at 30 m/s, the driving force becomes zero. Themass of the car is 800 kg. Calculate the deceleration of the car.

deceleration = ......................................[2]

opposing force600N driving force

in Fig. 10.1 if

Using Fig. 10.1, determine the pressure difference in Pa shown by the manometer.

Fig. 10.1

Fig. 10.1 shows a manometer used to measure the pressure difference between the air inside10

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a plastic container and the atmosphere outside.

A pressure difference of 100 Pa causes a one centimetre difference in water levels.

(a)

pressure difference = .............................Pa [1]

(b) State what changes, if any, occur to the distance h

(i) the manometer tube is narrower,

...................................................................................................................................

(ii) a liquid denser than water is used in the manometer.

...................................................................................................................................[2]

(c) The pressure difference measured by the manometer is caused by the force F. Thisforce is the weight of a student standing on the platform. The cross-sectional area of theplatform is 0.1 m2.

(i) State the formula that relates pressure, force and area.

...................................................................................................................................

(ii) Calculate the weight of the student.

weight = .........................................[3]

10

20

30

40

50

60

70

80

90cm

platformarea 0.1m2

flexibleplasticcontainer

air

force F

h

water

metre rule

manometer

State one change to the equipment in Fig.11.1 that would cause the baseplate to move

Fig. 11.1

A falling metal hammer is used to drive a hollow steel post into the ground, as shown in Fig.11.1.11

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Section BAnswer two questions from this section.

Use the lined pages provided and, if necessary, continue on the separate sheets available from the Supervisor.

The hammer is lifted by an electric motor and then falls freely to hit the baseplate.

(a) (i) State the law of conservation of energy.(ii) State the energy conversions that take place as the hammer falls, starting from the initial

potential energy of the hammer before it is dropped. [4]

(b) The metal hammer has a mass of 1500 kg and it hits the baseplate with a speed of 8.0 m/s.

(i) Calculate the kinetic energy of the hammer as it hits the baseplate.

(ii) State the initial potential energy of the hammer.

(iii) Calculate the height above the baseplate from which the hammer is dropped. Take g as10 N/kg.

[6]

(c) (i) In raising the hammer, the electric motor uses more energy than that stated in (b)(ii).State and explain two reasons why the motor uses more energy.

(ii)further into the ground each time the hammer falls.

[5]

ground

metal hammer

baseplate

rope from motor to lifthammer

hollow steel post

Fig. 12.2

Fig. 12.1

D and E the carriage turns through a bend at constant speed, as shown in Fig. 12.2. At E, brakes are

Fig. 12.1 shows a children’s ride. A carriage containing children is pulled up the slope by a motor. The12

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carriage stops at A and then runs down through B, C and D without further input of energy. Between

applied and the carriage slows to a stop at F. The height of the ride is 30 m at A and 10 m at C.

The mass of the carriage and children is 500 kg.Take the gravitational field strength as 10 N/kg.(a) (i) Discuss the energy changes that occur in the ride from A to D.

(ii) Calculate the maximum potential energy of the carriage and children.

(iii) Assuming that there is no friction between A and C, determine the kinetic energy of thecarriage and children at C. Show your working.

[9](b)

Between D and E, the carriage goes round part of a horizontal circle at constant speed.During this time the velocity of the carriage changes.(i) Explain how the carriage can have a constant speed but a changing velocity.(ii) State the direction of the force that acts on the carriage to make it move round the curve.

[3](c) Between E and F, a frictional force of 3000 N acts to slow the carriage. Calculate the

deceleration of the carriage. [3]

30m

10mB

C

D E

F

A

carriageviewed fromabove

E

D

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A train travels from one station to the next. It starts from rest at time t = 0 and acceleratesuniformly for the first 20 s. At t = 20 s it reaches its top speed of 25 m/s. It then travels at this speedfor a further 30 s before decelerating uniformly to rest. The total time for the journey is 60 s.

(a) (i) Sketch a speed-time graph for the motion of the train. Do not use graph paper. Put thespeed of the train on the y-axis and time along the x-axis. [3]

(ii) Write down the equation, in words, that relates acceleration, time and change invelocity. [1]

(iii) Explain what is meant by a uniform acceleration. [1]

(iv) Use your graph to calculate the deceleration of the train as it comes to rest. [2]

(b) Several forces act on the train when it is moving.

(i) Name the horizontal and vertical forces that act on the train and give the direction ofeach force. [4]

(ii) Explain whether the horizontal forces are balanced or unbalanced,

1. when the train accelerates,

2. when the train travels at constant speed,

3. when the train decelerates.

You may draw diagrams to help your explanations. [3]

(c) A second train has a non-uniform acceleration. Sketch a speed-time graph showing a non-uniform acceleration. Do not use graph paper. [1]