• 9702 June 2012 Paper 22 Worked Solutions | A-Level Physics

Question 1

{Detailed explanations for this question is available as Solution 1022 at Physics 9702 Doubts | Help Page 213 - http://physics-ref.blogspot.com/2015/10/physics-9702-doubts-help-page-213.html}

Question 2

A ball is thrown vertically down towards the ground and rebounds as illustrated in Fig. 2.1.

Question 3

{Detailed explanations for this question is available as Solution 614 at Physics 9702 Doubts | Help Page 121 - http://physics-ref.blogspot.com/2015/04/physics-9702-doubts-help-page-121.html}

Question 4

(a)

Pd across XY:

Total resistance in circuit = 8 + 12 = 20kΩ

Current = 12 / (20x10³)           or potential divider formula

p.d = [12/(20x10³)] x 12x10³ = 7.2V

(b)

Resistance LDR = 4.0kΩ. Current in ammeter:

Parallel resistance (across XY) = [(1/4) + (1/12)]^-1 = 3kΩ

Total resistance in circuit = 3 + 8 = 113kΩ

Current = 12 / (11x10³) = 1.09x10^-3A or 1.1x10^-3A

(c)

Intensity of light on LDR increased.

(i)

Change to ammeter reading:

The resistance of the LDR decreases. So, the total resistance (of the circuit) is less. Hence, current increases.

(ii)

Change to p.d across XY:

The resistance across XY is now less. So, there is less proportion of the 12V across XY. Hence, p.d. is less.

Question 5

{Detailed explanations for this question is available as Solution 626 at Physics 9702 Doubts | Help Page 124 - http://physics-ref.blogspot.com/2015/04/physics-9702-doubts-help-page-124.html}

Question 6

{Detailed explanations for this question is available as Solution 631 at Physics 9702 Doubts | Help Page 125 - http://physics-ref.blogspot.com/2015/04/physics-9702-doubts-help-page-125.html}

Question 7

{Detailed explanations for this question is available as Solution 641 at Physics 9702 Doubts | Help Page 127 - http://physics-ref.blogspot.com/2015/04/physics-9702-doubts-help-page-127.html}