From Mechanics
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Current revision
Solutions
1 (a)
| 44.1=21 9.8t2t= 4.944.1=3 sORs=21 9.8 32=44.1 Hits ground after 3 secondsAG | M1
A1
A1
(M1)
(A1)
(A1)
| (3 marks)
| M1: Use of constant acceleration
equation with v=0
A1: Correct equation
A1: Correct s
|
1 (b)
| v2=02+2 9.8 44.1v= 864.36=29.4mORv=0+9.8 3v=29.4 | M1
A1
A1
| (3 marks)
| M1: Use of constant acceleration equation with v=0
A1: Correct equation.
A1: Correct v.
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1 (c)
| Air resistance would slow the ball down.
| B1
| (1 mark)
| B1: Sensible statement about air resistance.
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| (7 marks)
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2 (a)
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| B1
| (1 mark)
| B1: Correct horizontal forces.
Ignore any vertical forces.
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2 (b)
| P=900N
| B1
| (1 mark)
| B1: Correct value for P.
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2 (c)
| P−900=2000 1.2P=2400+900=3300N | M1
A1
A1
| (1 mark)
| M1: Three term equation of motion
A1: Correct equation
A1: Correct P.
|
2 (d)
| 800−900=2000aa=2000−100=−0.05 ms−2Car is slowing down | M1
A1
A1
A1
| (4 marks)
| M1: Three term equation of motion
A1: Correct equation
A1: Correct a
A1: Correct statement
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| (9 marks)
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3 (a)
| R=20 9.8=196 N
| M1
A1
| (2 marks)
| M1: Use of R=mg
A1: Correct R.
|
3 (b)
| F=0.4 196=78.4 N
| M1
A1
| (2 Marks)
| M1: Use of F= R
A1: Correct F.
|
3 (c)
| 100−78.4=20aa=20100−78.4=1.08 ms−2 | M1
A1
A1
| (3 marks)
| M1: Three term equation of motion
A1: Correct equation
A1: Correct a.
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| (8 marks)
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4 (a)
|
| B1
| (1 mark)
| B1: Correct force diagram
|
4 (b)
| 100a=200−980sin5 a=100200−980sin5 =1.15 ms−2 | M1A1
M1
A1
| (4 marks)
| M1: Three term equation of motion
A1: Correct equation
M1: Rearranging equation.
A1: Correct a.
|
4 (c)
|
s=0 5+21 1.15 52=14.4 m
| M1
A1
A1
| (3 marks)
| M1: Using a constant acceleration equation
A1: Correct equation
A1: Correct distance.
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| (8 marks)
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5 (a)
| v=(6i+4j)+(0.2i−0.4j)t
| M1
A1
| (2 marks)
| M1: Use of v=u+at
A1: Correct expression
|
5 (b)
| 4−0.4t=0t=10 s | M1
A1
A1
| (3 marks)
| M1: Using j component equal to zero.
A1: Correct equation.
A1: Correct time.
|
5 (c)
| r=(6i+4j) 30+21(0.2i−0.4j) 302=270i−60jr= 2702+602=277 m | M1
A1
M1
A1
| (4 marks)
| M1: Using r=ut+21at2
A1: Correct position vector.
M1: Finding distance.
A1: Correct distance
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| (8 marks)
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KEY
M1: Method Mark
A1: Accuracy Mark following a method mark
B1: Accuracy Mark not following a method mark
AG: Answer Given in Question – Working must justify answer.
TOTAL: 40 Marks