8/9/2019 P3 Sabah 2007 Ans

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8/9/2019 P3 Sabah 2007 Ans

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(b)

R3

R2

R1

The resistence for each length of 200 cm of wire

= 200 x 0.03 = 6.0 Effective Resistence = R

=

=

++=

++=

2.0R

2

1

6

1

6

1

6

1

R

1

R

1

R

1

R

1

321

(4 marks)

(c)

m10x2.13.0x4

)(0.30x10

gradientx4

)(0.30x10

R

4

4R

7-23-

23-2

2

==

=

=

=

l

d

d

l (4 marks)

(d) The current must be small so that the temperature of the metal wire does not

change / remains constant.

(1 marks)

Section B

(12 marks)

3.(a) The water pressure increases when the depth of the sea increases. The pain in the

ear of the diver is due to the increasing pressure as he dives deeper.

(1 mark)

(b) The water pressure increase when the depth of the liquid increases. (1 mark)

(c) i. to investigate the relationship between the depth of the water and the

pressure exerted by the water.

ii. The manipulated variable : Depth of the water, h ( measure with ametre rule ), The responding variable : water pressure, The fixed variable :

density or type of liquid that is the same, similar containers.

iii. Water, metre rule, tin container and cork.

(10 marks)

8/9/2019 P3 Sabah 2007 Ans

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iv.

v. Method of controlling the manipulated variable:

The apparatus is set up as shown in the above diagram A hole is made on one of the wall of the tin

It is close with a cork stopper

The container is fill with water so that the level of the water, h, reaches 30cm.

Method of controlling the responding variable

The cork stopper is removed and the water shoot out.

The distance , x , of the water from the hole is measured

The experiment is repeated with different water levels, i.e. 25 cm, 20 cm, 15 cm

and 10 cm and using the same tin.

vi.

h / cm x / cm

30

25

20

15

10

vii. A graph of h against x is plotted

vii. as the water level (depth) increase, the water will spurt out the furthest.

4.

(a) The amount of radiation passing through an object is affected by itsthickness.(b) The thicker the object, the less radiation passes through.

(c)

(i) To investigate the relationship between the amount of radiation that passes

through an object and the thickness of the object..(ii) manipulated variable : thickness, t

responding variable : counts, n

fixed variable : distance between radioactive source and G-M tube(iii) G-M tube, -emitter, meter rule, cardboard of different thickness.

(1 marks)

(1 mark)

(10 marks)

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(iv)

(v) Method of controlling manipulated variable :The apparatus is set up as shown.

The counter is reset.

A piece of cardboard of thickness 1.0 mm is placed in between the source and the

G-M tube.

Method of measuring the responding variable :

The readings shown on the counter for 2 seconds is recorded.

The experiment is repeated using cardboard of thickness 2.0 mm, 3.0 mm, 4.0 mmand 5.0 mm

(vi)

Thickness , t / mm Reading on counter , n

1.0

2.0

3.0

4.0

5.0

(vii)

1.