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Answers Part A MEASUREMENT AND UNITS

1 a) kg b) m c) s d) A e) K 2 a) m2 b) m3 c) kg m s-2 (= N) d) m s-1 e) m s-2 f) kg m2 s-2 (= J) 3 a) 3 b) 5 c) 4 d) 6 e) 1 4 a) 5.67 x 103 b) 1.20 x 102 c) 4.70 x 107 d) 2.34 x 10-2 e) 6.94 x 10-5 f) 5.80 x 10-4 5 a) 12.6 mm b) 17.5 kg c) 263 J d) 2 500 MW e) 0.017 6 s f) 6.97 cm g) 8.67 x 104 m 6 2.60 x 104 L s-1 7 a) 0.883 hr b) 67.9 km h-1 c) 18.9 m s-1 8 500 s 9 1.08 x 109 km h-1

10 96 500 g = 96.5 kg

Part B VECTORS - Scale Drawing

1 238m at N220E 2 220km at S550W 3 186 m at N360E 4 267 N at N200E 5 a) 174 km b) 193 km 6 199 km/hr at N290E

Addition of Vectors

1 300 m north 2 150 m west 3 5.00 km, N36.9°E 4 6.71 km, S63.4° W 5 10.0 kN, S53° E 6 500 m, N 36.9° W 7 8.25 km, N 76° E 8 12.2 x 10-5 N, N 80.5° W

9 a) 7.07 m b) 7.07 m

10 a) 17.3 km b) 10.0 km

11 a) 25.0 N b) 43.3 N

12 a) 9.40 m s-2 b) zero (or 3.42 m s-2) KINEMATICS

Displacement-time graphs 1 a) 3.0 m s-1 north b) 0 – 2 s c) 2 – 5 s d) –1.0 ms-1 north=1.0 ms-1 south e) 8.0 s 2 a) i) 7.5m n, ii) 0m, iii) 7.5m n b) i) 3.75 m s-1 north, ii) 15 m s-1 south iii) 11.4 m s-1 north

c) i) 85 m, ii) 25 m north d) i) 7.7 m s-1 ii) 2.3 m s-1 north

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3 a) i) 7.5 m north ii) 10 m north iii) 20 m north iv) 7.5 m south b) i) 2.5 m s-1 northwards ii) 5.0 m s-1 northwards iii) 5.0 m s-1 northwards iv) 20.0 m s-1 southwards c) 15 m south d) 75 m e) 6.25 m s-1 f) 1.25 m s-1 south 4 a) b) 3.0 m s-1 southwards c) 3.33 m s-1 southwards d) 0 m s-1

Velocity - time graphs 1

a) 12.0 m s-1 northwards

b) 4.0 m s-1 northwards

c) 0.5 m s-2 southwards

d) 128 m north e) 8.0 m s-1

northwards 2

a) Describe b) 5.0 m s-1

southwards 10.0 m s-1 northwards

c) 2.5 m s-2 northwards

d) 15 m north e) 2.5 m s-1

northwards 3

a) 50 m s-1 North b)

i) 30 m s-1 North ii) 108 km/hr

North c)

i) 0 ii) -5.0 m s-2 N

(2.0 m s-2 S) iii) 20 m s-2 N iv) 25 m s-2 N

d) i) 80 m N ii) 110 m N iii) 170 m N iv) 220 m N

e) 20 m s-1 North f) 22 m s-1 N g) 15 m s-1 N h) Explain

4 a)

i) 12 m s-1 North ii) -4.0 m s-1 N

(4.0 m s-1 S) b) 16.0 m s-1 N

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c) i) 64 m N ii) 96 m N iii) 56 m N iv) 72 m N

d) i) 2.0 m s-2 North ii) 0

e) i) 3.11 m s-1 N ii) 2.57 m s-1 N

f) 200 m g) 7.14 m s-1 h) 10 s, 14 s i)

5 a) Car: 108 km/h,

MC: 144 km/h b) +2.0 m s-2 c) 40.0 s d) 1.80 km

6 Graphs

Acceln. - time graphs 1

a) iv b) i c) ii d) iii

2 Graphs

1 Linear Motion 1 a) 20 m s-1 b) 54 km h-1 west c) 1.5 m s-2 2 a) 0.128 m s-2 east b) 7.05 m east 3 2.04 m s-2 4 a) 2.52 s b) 2.49 m s-2 north 5 a) 7.31 m s-2 along b) 366 m c) 263 km h-1 6 13.9 s 7 55.0 m 8 a) 6.0 cm b) 10 cm 9 a) 1.71 m s-1 b) 6.15 km h-1 c) zero

10 a) 1.43 m s-2 west b) 13.6 s

11 a) 11.1 m s-2 SE b) 203 m

12 145 M 13 19.0 m s-2 14

a) 5.0 m s-1 south b) c) 25 m

15 609 m s-2 upwards 16

a) 26.4 m s-2 upwards b) less accln = less force on egg

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Vertical Motion 1 a) 0 b) 5.05 s c) 49.5 m s-1 down 2 a) 54.3 m s-1 down b) 130m 3 a) 9.80 m s-2 down b) 44.1 m c) 32.8 m s-1 d) 32.8 m s-1 down e) 10.2 s f) 6.39 s 4 a) 49.1 m s-1 b) 123 m 5 4.04 m 6 a) 2.97s b) 43.2 m c) 5.94 s d) 1.95 s e) 3.99 s f) 29.1 m s-1 down 7 a) 10.0 m s-1 up b) 205 m above grd. 8 a) 16 m s-1 b) 1.6 m s-2 c) 10 s d) 80 m e) 13.0 m 9

10 a) 1.58 m s-2 down b) 25.9 m s-2 down c) i) 44.3 m s-1 down ii) 17.8 m s-1 down iii) 72.0 m s-1 down

Motion on an Inclined Plane 1 a) 4.15 ms-2 b) 6.94 ms-2 c) 5.99 ms-2 d) 0.00 ms-2 e) 9.06 ms-2 2 a) 37.7° b) 19.3° c) 90.0° d) 0.0° 3 a) 3.52 ms-2 b) 21.2 ms-1 c) 7.89 s 4 a) 0.855 ms-2 b) 5.00° 5 13.5° 6 3.59 ms-2 7 20.5 ms-2

Projectile Motion 1 a) horizontal b) vertical c) i) no effect ii) decreases 2 a) Neither. Hit at same time.

b) Hits c) Ball 2 3 a) 0 m s-1 b) 190 m down 4 a) 9.80 ms-2 down b) 0 c) 490 m down d) 9.99 s e) 0 f) 160 ms-1 g) 160 ms-1 h) 1598 m

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i) Vertically down (straight beneath him)

5 a) 1.14 s b) 16.0 m c) 14.0 m s-1, 11.2 m s-1 d) 17.9 m s-1 at 38.70 below horizontal.

6 a) 5.0 s b) 35 m c) 49.5 m s-1 at 81.90 below horizontal

7 a) 60 m b) 39.5 m s-1 at 82.70 below horizontal

8 Yes, his bullet will hit the monkey.

9 Explain 10

a) Explain b) 5.1 m

Part C NEWTON’S LAWS Newton I – Discuss Newton II

1 a) 2.0 m s-2 b) 10 m s-1 c) 12 m s-1 d) 7.0 m s-1 e) 35 m 2 a) 6.0 N down b) 0.75 N west c) 6.3 N south 3 217 N in the direction of motion

4 13 900 N opposite to direction of motion

5 11 574 N in direction of motion

6 a) 10 m s-2 north b) 4.0 m s-2 left c) 7.5 m s-2 N530W 7 10 N north 8 250 N against direction of motion

9 2.0 N to left 10 9.81 m s-2 upwards 11

a) 107.3 m s-1 b) 8580 N in direction of motion

c) 1716 N against motion

d) 10 296 N in direction of motion

12 a) 300 kN against motion

b) one-third of force c) Increase stopping distance Therefore decrease stopping force

13 2.0 m s-2 14

a) 7 000 N forwards b) 1.0 m s-2 “ c) 2 000 N “ d) 5 000 N “

15 a) 0.25 m s-2 b) 2.5 kN forwards

Newton III 1 – 8 Discuss

9 a) 30.0 N east b) 5.0 m s-2 eastwards c) 5.0 m s-2 eastwards d) 20 N east e) 10 N west f) 10 N east

10 a) 2 000 N east b) 2 000 N east c) 5.0 m s-2 eastwards d) 5.0 m s-2 eastwards e) 1 500 N east f) 500 N west g) 500 N east h) Labels etc

11 a) 800 n east b) 800 n west c) 800 n west

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d) 2.0 m s-2 westwards e) 2.0 m s-2 westwards f) 400 n west g) 2 600 west h) 2 600 n east i) Labels j) Labels

Ropes, Lifts & Parachutes

1 a) 196 N down b) 196 N up c) 0 d) 196 N up 2 a) 4.0 N up b) 200 N up 3 a) 5.5 m s-2 upwards b) 385 N upwards c) 1 071 N upwards d) 686 N upwards 4 0.0270 N up 5 a) 5 880 N up b) 5 880 N up c) 6 150 N up d) 5 610 N up 6 5150 N up 7 Discuss 8 2.2 m s-2 9 a) Explain b) 2.26 m s-2 c) 6.01 m s-1

General Newton’s Law 1 150 kg 4 a) Top b) Bottom

12 207 km h-1 PART D MOMENTUM Momentum & Impulse

1 a) 0.96 kg ms-1 east b) 3.87x10-20 kg m s-1 upwards

c) 15 000 kg m s-1 southwards

2 a) about 100 kg m s-1 b) about 2 N-s 3 a) 630 kg m s-1 north b) 0.55 kg m s-1 down 4 a) i) 3.0 N-s upwards ii) 400 N-s southwest b) i) 3.00 kg m s-1 ii) 400 kg m s-1 5 a) 60 kg m s-1 east b) 20 m s-1 6 a) 8.0 N-s east b) 8.0 kg m s-1 east c) 32 m s-1 east 7 a) 0.48 N-s south b) 0.48 kg m s-1 south c) 2.4 m s-1 south 8 120 m s-1 west 9 140 N south

10 1210 N south 11 100 s 12

a) 5 500 kg m s-1 west b) 91.7 N west

13 a) 1 598 kg b) 31 960 kg m s-1 south c) 49.9 s

14 a) 20 400 kg m s-1 east b) 300 N east

15 a) 4.0 N north b) 19 kg m s-1 north c) 3.8 m s-1 north

16 a) 4.5 N-s b) 4.5 kg m s-1 c) 90 m s-1 d) 450 N e) 450 kg m s-1 /sec

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17 a) 1.25 kg m s-1 north b) 1.75 m s-1 north

18 a) 26.1 J b) 1.74 kg m s-1 north c) 1.74 kg m s-1 south d) 3.48 kg m s-1 south e) 33.14 N south f) 33.14 N north

Conservation of Momentum

1 1.2 kg m s-1 east a) 1.2 kg m s-1 east b) 0.48 m s-1 2 a) 0 b) 0 c) 1.0 m s-1 east 3 1010 m s-1 north 4 6.67 m s-1 west 5 2.00 m s-1 north 6 0.58 m s-1 east 7 17.8 m s-1 west 8 10.0 m s-1 south 9 7.50 m s-1 up

10 2.91 m s-1 west 11 11.6 m s-1 west 12 10.0 cm s-1 south

PART E

WORK, POWER & ENERGY

1 a) 163 J b) 136 J c) 0 J 2 56 J 3 7.37 kJ 4 400 J 5 14.24 m s-2 north 6 622 J 7 707 J 8 59 290 J 9 a) 202.5 J b) 697 kJ

10 a) 600 kJ b) 600 kJ

11 a) 1.26 MJ b) 1.26 MJ c) 6.90 m s-2 d) 65.3 m e) 19 310 N

12 a) 1.0 J b) 1.0 J c) 3.16 m s-1

13 a) 50 J b) 80 J c) 3.27 m s-1

14 a) 80 J b) 160 J c) 160 J d) 5.67 m s-1 e) 430 J f) 9.27 m s-1

15 a) Describe b) describe c) 10 J d) 13 J e) 3.6 m s-1

16 439 W 17 39.2 sec 18

a) 2.5 MJ b) 250 kW

19 a) 150 kJ b) 30 kW c) 120 kW d) 450 kJ

20 a) 93 596 J b) 93 596 J c) 781 W d) 2 603 W e) 218 614 J

21 6.67 s Consvn of Energy

1 1.98 m s-1 2 a) 49.05 J b) 49.05 J c) 49.05 J

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3 a) 675 kJ b) 0 c) 675 kJ d) 9000 N east 4 Xx a) 7.50 J b) 3.06 J c) 4.44 J d) 1.48 N south

5 a) 30.6 J b) 30.6 J c) 30.6 J d) 62.4 m e) 30.6 J f) 20.8 J 6 a) 2.0 J b) 0 c) 2.0 J d) 0.204 m e) 0.596 m 7 a) 234 m b) 72 km h-1 c) no change d) carriage would not rise so high & be slower on returning to the bottom.

8 a) 750 J b) 1 339 J c) 1 339 J d) 161.4 J e) 2.32 m s-1 f) 6.68 m s-1 9 a) 4 800 J b) Point B c) 11 772 J d) 16 572 J e) 10.7 m s-1

10 6.66 m s-1 11

a) 58 100 J b) 581 N

Part F NUCLEAR PHYSICS Atomic and Nuclear

1 a) Uranium (U) b) Hydrogen-2 (deuterium)

c) Radium (Ra) d) Phosphorus (P) 2 , 3

He-3 He-4 e 2 2 p 2 2 n 1 2

4 a) 1,1 b) 6,6 c) 8,9 d) 11,12 e) 16,16 f) 47,60 g) 53,74 h) 92,146

Half Life 1 0.156 mg 2 45 hours 3 11 460 years 4 222 days 5 96 MBq 6 0.125 g 7 5.66 x 1018 8 explain 9

a) i) 80 µg ii) 40 µg iii) 20 µg iv) 10µg b) It is converted (“transmuted”) into another element ( ) 10

a) → + + γ b) 300 days 11 i) 140 mg, 384 Bq ii) 35 mg, 96 Bq b) → + 12 320 mg 13 0.5 MBq

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14 2 days 15 a) 0.8 GBq b) 0.4 GBq c) 0.00625 Gbq = 6.25 MBq α, β and γ Decay

1 , , , γ 2

a) → +

b) → +

c) → +

d) → +

e) → + γ f) → +

g) → + h) → +

3 → + etc 4 → + etc 5 → +

→ + X = Th-234, X’ = Pa-234

6 a) → + b) → + c) → +

Nuclear Equations

1 a) + → + b) + → + Proton

c) + → + d) + → + 2 a) + → +

b) + → + c) + → + d) + → + 3 a) + → + b) + → + c) + → + 4 a) + → + b) + → + c) + → + 5 a) + → + b) proton 6 No charge, therefore not repelled by nucleus. Fission & Fusion

1 Discuss 2 a) 6 b) 4 3 A = 85, Z = 35 4 + → + + 2

ie 2 neutrons

5 Discuss 6 Discuss 7 One-third 8 a) Extra neutrons i) + → + + energy ii) + → + + energy iii) + → + + energy 9 4 → + 2 + 2 γ + energy

10 a) + → b) + → c) + →

Radio-isotopes Discuss