Answer Scheme Final Exam 2010FORM 4 PHYSICS (Paper 3)

Section A

Question Answer Marks1(a) (i) Object distance, u 1

(ii) Image distance, v 1(iii) Focal length , f // thickness of convex lens 1

(b)

Tabulate data

1. Shows a table contain 4 quantities : u , v, and

2. State the correct unit for u , v, and

3. All values of v are correct and consistent to 1 decimal places.

4. Values of are consistent to 3 decimal places.

5. Values of are consistent to 3 decimal places.

√ m1

√ m2

√ m3

√ m4, √ m5

√ m6, √ m7

(c)

Draw the graph of against

1. The responding variable, at y axis, the manipulated variable, at

x axis2. States the unit of the variable correctly3. Both axis with the even and uniform scale4. 4 -1 points correctly plotted All of 5 points correctly plotted.5. A smooth best fit straight line6. Minimum size of the graph is 10 cm x 8 cm

√ 1

√ 2√ 3√ 4, √ 5√ 6√ 7

1

(d)is decreases linearly to

* If the graph that has been plotted does not cross axis-y, cancel any answer in (d).

1

Total 16 M

2 (a)(i) 1) Draw the extrapolation line from t = 1 min to the y-axis2) State the correct value of Ɵ with correct unit 28.5°C 0.5 °C

1

1(ii) 1) State the correct relationship of Ɵ and t

Ɵ increases linearly with t1

(iii) 1) Construct a sufficiently large triangle (4x4)2) Make the correct substitution 69-37 5-13) State the correct value with unit 8.0°C min-1

11

1

b(i) 1) Make correct substitution E=P x t = 200 x 5 x 602) State correct answer with unit 60 000 J

1

1

(ii) 1) Make the correct substitution C = 60 P = 60 x 200 mM 8 x 0.42) State the correct answer 37503) State the correct unit J kg-1°C-1

1

1

1

(c) 1)State one suitable precaution-Eye perpendicular to scale of thermometer to avoid parallax error-Repeat experiment 4 times and calculate average-Stir cooking oil before taking thermometer reading to get uniform

temperature

1

Total 12 M

Section B

2

3 (a) (b)

(c)(i)

(ii)

(iii)

The length of the spring depends on the mass of the babiesThe bigger the mass of the attached weight, the longer the length of the spring.

To study the relationship between the mass attached and the length of a spring

Manipulated variable : mass of weight, mResponding variable : length of spring, l // extension of spring, eFixed variable : diameter of spring // spring constant

List of apparatus/material:slotted masses, retort stand, metre rule, pin and spring.

11

1

11

1

(iv)Arrangement of apparatus

1

(v)

(vi)

Method of controlling the manipulated variableI. A slotted mass of 100 g is hooked at the lower end of the spring

Method of measuring the responding variableII. The length of the spring, l is measured by using metre rule

Repeated experimentIII. Experiment is repeated with slotted weights of mass

and

1

1

1

Mass, length of spring, l / cm100200300400500

3

(vii) A graph of l against m is drawn

l /cm

1

1

TOTAL 12

4 (a) (b) (c)(i)

(ii)

(iii)

The volume of the balloon depends on the pressureThe volume of a gas increases as the pressure decreases

To investigate the relationship between pressure and volume of gas at constant temperature

Manipulated variable : Volume of gas, VResponding variable : Pressure of gas, PFixed variable : Temperature of gas // mass of gas

List of apparatus/material:Syringe, Bourdon gauge, rubber tube

11

1

11

1

(iv)Arrangement of apparatus

1

4

gm /

(v)

(vi)

(vii)

Method of controlling the manipulated variableI. The piston of the syringe is adjusted until the volume, V= 100cm3

Method of measuring the responding variableII. The pressure, P on the Bourdon gauge is recorded

Repeated experimentIII. The steps are repeated by reducing volume, V = 90 cm3, 80 cm3, 70

cm3 and 60 cm3

Volume, V /cm3 Pressure, P / Pa10090807060

A graph of P against V is drawn

1

1

1

1

1

TOTAL 12M

5

Volume, V / cm3

Pressure, P / Pa