LINEAR MOTION
1. (a) (i) arrow pointing to the left; 1
(ii) A; 1
(b) (i) both points plotted correctly;
line completed on graph; 2
(ii) 20 and 30;
[Accept any two values between 20 and 30] 1
(iii) 0 and 20;
[Accept any two values between 0 and 20]
line is steepest/calculation/reference to travelling greater distance
in same or less time; 2
[7]
2. (a) An explanation to include:
1. van plus reference to change in speed;
2. in same time/ 5 s / 10 s; 2
(b) An explanation to include:
1. same mass/weight/eq;
2. bigger acceleration;
[Accept also F = ma argument) 2
[4]
3. (a) An explanation to include three from:
1. initially driving force greater than resistive force;
2. resistive force increases;
3. resultant or unbalanced force decreases/acceleration decreases
(in correct context);
4. forces equal in size at constant speed/resultant force is zero; 3
(b) greater acceleration/less driving force;
since less mass (F=ma); 2
(c) (i) KE = ½ m v2 = ½ 85 122;
= 6120;
J; 3
energy
(ii) time = power = 6120 J ;[Allow ecf]
200 W
= 34 s; 2
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(d) (i) 20 (J) as heat/waste energy/to atmosphere/surroundings; 1
useful energy out
(ii) efficiency = ;
energy in
180J
= ;
200J
= 0.90 / 90%; 3
(iii) all the energy goes to atmosphere/surroundings/work done
against/overcoming friction; 1
[Reject energy lost as heat/friction unqualified]
[15]
4. (a) drag/resistance/force/push/thrust/upthrust;
air/atmosphere;
[Reject wind/friction] 2
(b) 56; 1
(c) (i) pull of Earth/weight/gravitational pull/downward (pull) greater than upward
(push)/there is resultant force downwards;
[Allow gravity] 1
(ii) both forces the same/balanced/equal/resultant force is zero/OWTTE; 1
(d) (i) speed decreases;
new lower terminal velocity/horizontal region shown;
(Independent marking points) 2
(ii) An explanation to include three from:
air resistance increases;
at start upward force greater than downward force;
eventually forces balance;
larger surface area;
air resistance decreases as parachutist slows down; 3
[10]
5. (a) An explanation to include:
1. it increases;
2. cyclist moves further in same time interval/each time; 2
(b) 12 m; 1
(c) X marked anywhere between 21 and 27 m;
[Reject 28 m] 1
[4]
6. (a) (i) friction (between book and table top); 1
(ii) (transferred to) heat;
[Ignore sound]
[Reject other answers] 1
(b) forward push of ground/force due to ground/forward push on shoe/friction;
[Ignore reaction with ground] 1
[3]
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7. (a) A description to include:
1. upward push/reaction/thrust;
2. of the ground on the athlete; 2
(b) (i) 0.39 (s);
[Accept 0.4 (s)] 1
(ii) A calculation to include:
= area below graph / average velocity time;
1
= 3.8 0.39;[Allow ecf from (b)(i) – 0.76(m)]
2
= 0.74 (m);
[If 4.0 used for velocity then the first and the third marks
can be credited] 3
(iii) A calculation to include:
v u ;
1. acceleration =
t
3 .8 7 .6
2. substitution of correct data, eg ; [Allow ]
0.39 0.78
3. = 9.7 m/s2; [Accept –9.7 m/s2] 3
(iv) downwards;
negative gradient/backwards slope/athlete slowing down/retardation/deceleration; 2
(v) A calculation to include:
1. F = ma;
2. = 65 kg 9.7 (m/s2);[Allow ecf from b(iii)]
3. = 630 – 633 (N);
[Accept either 65 10 m/s2 = 650 N for 2 marks
or 65 9.81 m/s2 = 638 N for 2 marks] 3
(vi) downward pull of the Earth/gravitational pull;
[Reject gravity] 1
[15]
8. (a) F = m × a / W = m × g;
= 70 × 10;
= 700 N; 3
(b) speed constant;
upward force = downward force/
forces balanced/from F = ma if a = 0; 2
(c) A description and an explanation to include:
opens parachute at C;
drag force increased/upward force increased;
lower terminal velocity;
plus 1 communication mark for using a suitable structure
and style of writing; 4
(d) shows lower terminal velocity at D;
shows longer time to land; 2
[11]
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9. (a) 600 m; 1
(b) 200 – 100;
100 m; 2
(c) it is a straight line; 1
(d) Y;
greater slope/steeper line; 2
[6]
10. (a) distance increases as speed increases / it increases / OWTTE; 1
(b) 138 – 140 m; 1
(c) below the first line;
curve of similar shape to graph; 2
[Second mark conditional on first]
(d) A description to include:
1. kinetic / movement energy;
2. (to) thermal (heat) /sound energy; 2
[List after kinetic energy scores 0 marks for the second marking point]
(e) some kinetic energy transferred to gravitational potential energy /
weight is extra retarding force /
gravitational potential energy increases / gravitational pull / OWTTE; 1
[7]
11. (a) 0 – 2 (seconds); 1
(b) upwards;
lift is slowing (even though it is falling); 2
[Direction must be mentioned to score second marking point]
(c) area below graph is height (distance travelled)
distance = speed × time;
1 × 1.8 + 6 × 1.8 + 1 × 1.8; 3
14.4 (m); [Allow ecf]
[Accept 8 × 1.8 14.4 m for 3 marks]
[6]
12. (a) points plotted correctly;; [Deduct 1 mark for each error] 2
[Line not necessary]
(b) 3 (m/s); 1
change in velocity
(c) (i) acceleration = ; 1
time taken
v velocity speed
[Accept a = or or ]
t time time
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3
(ii) acceleration = ; [Allow ecf from part (b)]
15
= 0.2 (m/s2); 2
[6]
13. (a) (i) area below graph / average velocity (speed) × time; 1
[Reject velocity × time]
(ii) A calculation to include:
1. Distance = ½ × 15 × 3;
2. = 22.5 (m) ; 2
[Allow 45 m for 1 mark]
(b) A calculation to include:
change in velocity
1. acceleration = ;
time
v velocity speed
[Accept a = or or ]
t time time
2
2. = = 0.2 (m/s2);
10
3. force = mass × acceleration;
4. = 1.2 × 105 × 0.2 = 2.4 × 104 N ;
[Allow ecf if acceleration calculated and evidence of this is shown]
[7]
14. (a) plots;;
[Deduct 1 mark for each error] 2
(b) straight line / goes up equally / uses data table; 1
(c) A calculation to include:
1. speed = gradient / slope / distance/time;
750
2. = / spot value from graph or table;
25
3. = 30 m/s; 3
(d) An explanation to include:
1. friction / drag / air resistance present;
2. no unbalanced force / equals driving force; 2
[8]
15. (a) (i) 90; 1
(ii) (39-40); 1
(iii) An explanation to include:
1. (15-16) s;
2. slows down / less (lower) speed / reference to graph /
decelerate;
[Reject change in speed] 2
(iv) 20; 1
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(b) A description to include three from:
1. F = mg;
2. F increases;
3. F > mg
F decreasing;
4. F = mg;
5. mg = constant;
[OWTTE in right context] 3
[8]
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