Monday, May 24, 2010

Answer

F4
1b) i) Increases
ii) Because the gradient of the graph increases
c) i) Because the gravitational acceleration is 10 ms-2

ii) Reduces due to air resistance

2a) i) going up hill

ii) going down hill

b) i) 125 m (area under the graph from 10 to 20s )

ii) – 1 ms-2

3a) – 80 kg ms-1

b) No, because the total momentum in a closed system is constant

4a) i) 3

ii) weight, reaction force and string tension

b) string tension = 1000 N

reaction force = 866 N

5a) i) with and without air resistance

ii) air resistance is reducing the speed of motion

b) fall at the same time

6a) the product of mass and acceleration

b) F – f = ma

c) i) F3 = water resistance

ii) 466 N

iii) 2.33 ms-2

7 a) 4500 x 0.1 = 450 J

b) 25 x 2π x 0.15 x 40 = 942 J

c) 450 / 942 x 100 % = 47.7 %

d) 1. as heat energy

2. as sound energy

e) Yes because it reduce the mass of the screwjack

f) 1. Ligher platform

2. reducing frictional force

8 a) i) P

ii) highest spring constant

b) 1. Diameter of the spring

2. diameter of the wire

c) Can. It will help to withstand a higher load

d) Because the elastic limit of the spring is exceeded

e) k = F/x = 500 Nm-1

F5

1. D 2. C 3. A 4. B 5. D 6. D 7. C 8. C 9. C 10. B

11. B 12. D 13. B 14. B 15. A 16. D 17. D 18. D 19. D 20. A

1 a) Small surface area. Charges are accumulated at low surface area

b) n = Q/e = 6.25 x 1019

2 a) Ability of a conductor to resist current flow

b) voltmeter parallel to the bulb while the ammeter series to the bulb

c) the reading of the voltmeter divide with the reading of the ammeter

d) R = V/I = 10

3 a) i) 0.13 A

ii) 0.33 A

b) 22

c) i) 30

ii) 0.24 A

4a) i) It needs 240 V of input potential difference to generate 2000 W of output power

ii) I = P/ V = 8.33 A

iii) 9 A because the maximum current flow is 8.33 A

6 comments:

I`m miN said...

thanks sir for the answers ~
but y the no.14 ans is B 1??

Crystal Pui Yan said...

why x form 3? xDxD

Loke 地行者 said...

Sorry lor, this year i teach F4 and F5 only

yen said...

sir, you know about add maths project 2010?

Loke 地行者 said...

2010 Add Math project ?
Not sure, if have, i can help

yen said...

got!
how can i give u the question?