Post on 22-Jan-2021
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M107 assessment Kinematics 1 SOLUTIONS
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Do the questions as a test – circle questions you cannot answer
Red
1) Frederica drops a stone down a well. She measures the time it takes to hit the water
at the bottom as 4 seconds. Estimate the depth of the well and state two
assumptions you have made in modelling your solution
[4]
2) A Ferrari accelerates constantly for 3 seconds to reach the speed limit of 30 mph
If the distance covered in the 3 seconds is 20 m, calculate the initial speed of the
car. Use 1 mile = 1.6 km [3]
M107 assessment Kinematics 1 SOLUTIONS
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3)
A car moves along a straight horizontal road. At time 𝑡 = 0, the velocity of the
car is U ms-1. The car then accelerates with constant acceleration a ms-2 for 𝑇
seconds. The car travels a distance 𝐷 metres during these T seconds.
The diagram shows the velocity-time graph for the motion of the car for 0 ≤ 𝑡 ≤ 𝑇. Using the graph, show that 𝐷 = 𝑈 𝑇 + ½ 𝑎𝑇2 .
(No credit will be given for answers which use any of the kinematics (suvat)
formulae listed under Mechanics in the AS Mathematics section of the formulae
booklet.) [4]
4) A man throws a stone on a level playing field. Assuming the stone is thrown at
initial speed 18 m/s, from a height of 2 m and at an angle of 40, how far will it
have travelled horizontally from the man by the time it hits the ground? [6]
M107 assessment Kinematics 1 SOLUTIONS
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5) A girl throws a stone which breaks a window 2 seconds later. The speed of
projection is 20 ms-1 and the angle of projection is 60. Assuming that the stone
can be modelled as a particle moving with constant acceleration, find the
horizontal and vertical components of the velocity of the stone just before impact [4]
Amber
6) Figure 1
Figure 1 shows the speed-time graph of a cyclist moving on a straight road over a 7
s period.
The sections of the graph from t = 0 to t = 3, and from t = 3 to t = 7, are straight
lines.
The section from t = 3 to t = 7 is parallel to the t-axis.
State what can be deduced about the motion of the cyclist from the fact that:
a) the graph from t = 0 to t = 3 is a straight line, [1]
b) the graph from t = 3 to t = 7 is parallel to the t-axis. [1]
c) Find the distance travelled by the cyclist during this 7 s period. [4]
5
v (m s–1)
t (s) O 7 3
2
M107 assessment Kinematics 1 SOLUTIONS
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7) A car is moving along a straight horizontal road. At time t = 0, the car passes a
point A with speed 25 m s–1. The car moves with constant speed 25 m s–1 until t =
10 s. The car then decelerates uniformly for 8 s. At time t = 18 s, the speed of the
car is V m s–1 and this speed is maintained until the car reaches the point B at time
t = 30 s.
a) Sketch a speed–time graph to show the motion of the car from A to B [3]
Given that AB = 526 m, find
b) the value of V, [5]
c) the deceleration of the car between t = 10 s and t = 18 s. [3]
M107 assessment Kinematics 1 SOLUTIONS
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8) A firework rocket starts from rest at ground level and moves vertically. In the
first 6s of its motion, the rocket rises 29m. The rocket is modelled as a particle
moving with constant acceleration ams–2. Find
a) the value of a, [2]
b) the speed of the rocket 6s after it has left the ground [2]
After 6s, the rocket burns out. The motion of the rocket is now modelled as that of
a particlemoving freely under gravity
c) Find the height of the rocket above the ground 9s after it has left the ground [4]
M107 assessment Kinematics 1 SOLUTIONS
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9) A racing car moves along a straight horizontal road with constant acceleration. It
passes the point O with speed 12 m/s. It passes the point A 5s later with speed 58 m/s
a) Find the acceleration of the car [2]
b) Find the distance OA [3]
The point B is the midpoint of AO
c) Find the speed of the car when it passes point B [3]
M107 assessment Kinematics 1 SOLUTIONS
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10) A firework rocket starts from rest at ground level and moves vertically. In the first
3 s of its motion, the rocket rises 27 m. The rocket is modelled as a particle
moving with constant acceleration a m s–2. Find
a) the value of a, [2]
b) the speed of the rocket 3 s after it has left the ground.
[2]
After 3 s, the rocket burns out. The motion of the rocket is now modelled as that of
a particle moving freely under gravity.
c) Find the height of the rocket above the ground 5 s after it has left the ground.
[4]
M107 assessment Kinematics 1 SOLUTIONS
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Green
11)
A car moves along a straight horizontal road. At time 𝑡 = 0, the velocity of the
car is U ms-1. The car then accelerates with constant acceleration a ms-2 for 𝑇
seconds. The car travels a distance 𝐷 metres during these T seconds.
The diagram shows the velocity-time graph for the motion of the car for 0 ≤ 𝑡 ≤ 𝑇. Using the graph, show that 𝐷 = 𝑈 𝑇 + ½ 𝑎𝑇2 .
(No credit will be given for answers which use any of the kinematics (suvat)
formulae listed under Mechanics in the AS Mathematics section of the formulae
booklet.) [4]
M107 assessment Kinematics 1 SOLUTIONS
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12) A car moves along a horizontal straight road, passing two points A and B. At A the
speed of the car is 15 m s–1. When the driver passes A, he sees a warning sign W
ahead of him, 120 m away. He immediately applies the brakes and the car decelerates
with uniform deceleration, reaching W with speed 5 m s–1. At W, the driver sees that
the road is clear. He then immediately accelerates the car with uniform acceleration
for 16 s to reach a speed of V m s–1 (V > 15). He then maintains the car at a constant
speed of V m s–1. Moving at this constant speed, the car passes B after a further 22 s.
a) Sketch a speed-time graph to illustrate the motion of the car as it moves from A to B. [3]
b) Find the time taken for the car to move from A to B. [3]
The distance from A to B is 1 km.
c) Find the value of V. [5]
M107 assessment Kinematics 1 SOLUTIONS
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13) A ball is projected vertically upwards with speed 21 m s–1 from a point A, which is
1.5 m above the ground. After projection, the ball moves freely under gravity until
it reaches the ground. Modelling the ball as a particle, find
a) the greatest height above A reached by the ball, [3]
b) the speed of the ball as it reaches the ground, [3]
c) the time between the instant when the ball is projected from A and the instant when
the ball reaches the ground
[4]
M107 assessment Kinematics 1 SOLUTIONS
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14) A and B are two bus stops on a straight horizontal road. A bus passes A travelling
towards B at a constant velocity of 16ms−1. The bus continues at this velocity
for T seconds. It then decelerates at a constant rate for the next 7s until it comes to
rest at B
a) Sketch a velocity–time graph for the motion of the bus [2]
b) Find the deceleration of the bus [2]
c) Find, in terms of T, the distance travelled by the bus [3]
6s after the bus passes A, a car leaves A and travels towards B. The car moves
from rest with a constant acceleration of 36ms−2 The car and bus reach B at the
same time
d) Find the distance between A and B [7]
M107 assessment Kinematics 1 SOLUTIONS
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15)
A boy throws a stone with speed U m s−1 from a point O at the top of a vertical
cliff. The point O is 18 m above sea level. The stone is thrown at an angle α
above the horizontal, where tan ∝=3
4 .
The stone hits the sea at the point S which is at a horizontal distance of 36 m from
the foot of the cliff, as shown
The stone is modelled as a particle moving freely under gravity with g = 10 m s−2
a) Find the value of U, [6]
b) Find the speed of the stone when it is 10.8 m above sea level, giving your answer
to 2 significant figures [5]
c) Suggest two improvements that could be made to the model. [2]
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TOTAL 112
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