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S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Introduction I
Data of F (force) and L (Length of spring) in an experiment are collected as below.
(i)
(ii)
L
1
3
4
6
10
F
3.2
1.4
1.2
1.0
0.8
1/L
Complete the above table and plot F against 1/L and draw the best straight line.
Find the slope, m and the equation to describe the relationship between F and 1/L
i)
ii)
The slope of the graph, m :
The equation for the graph :
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Introduction II
A student drops a stone from various heights (h/m). The heights and the corresponding time taken (t/s) by
the stone to reach the ground are recorded in the following table.
h (m)
5
20
45
60
t (s)
1
2
3
3.5
t2 (s2)
i.
Complete the table, plot h against t2 and draw the best fit line (Best straight line).
ii.
Find the slope of the graph, m and express h and t2 in an equation.
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Electricity I
Use the information provided below to evaluate (評估
評估,e/’va/lu/ate
-verb, e/,va/lu/’a/tion-n.) each light
評估
bulb. Decide on which bulb you would choose giving clear reasons. Both bulbs are of equal brightness.
Feature
Power
Lifetime
Cost
Cost of electricity per unit
Tungsten Filament
100W
1000 hr
$6
$0.9
Flourescent tube
20W
5000 hr
$35
$0.9
Show your working steps below (in details)
Item
Tungsten Filament
Total number of light bulbs
required for 5000 hours
Total cost for light bulbs
Flourescent tube
Total Power consumed in 5000
hours (in kWh)
Total Cost of Electricity for 5000
hours
Total cost for 5000 hours
Decision and reason :
If each flourescent tube can only last for 3000 hours, which type of light bulb will you choose?
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Electricity II
Multiple Choice: (You must show your working steps in the space of each question)
For Questions 1-4
A current of 3 A passes through a conductor for 4 minutes. The voltage across the conductor is 12 V
1.
The quantity of charge passes through the conductor is
A.
12 C
B.
36 C
Applying equation : Q = I x t
C.
48 C
Then Q = (
)x (
)
D.
144 C
=
E.
720 C
2.
The resistance of the conductor is
A.
12Ω
B.
8Ω
Applying equation : R = V/I
Then
R=(
)/(
C.
6Ω
=
D.
4Ω
E.
3Ω
)
3.
The total energy used by the conductor is
A.
8640 J
Applying equation : E =
B.
720 J
C.
144 J
D.
48 J
E.
36 J
4.
The power dissipated of the conductor is
A.
3W
Applying equation :
B.
4W
C.
12 W
D.
36 W
E.
48 W
5.
We have four identical resistors. The resistance of each resistor is 4 ohms. Which of the following combinations gives
the least resistance across X and Y ?
A.
X
Y
B.
X
Y
X
Y
C.
D.
X
Y
E.
X
Y
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
For Questions 6-8
In the circuit shown on the right, the reading of the ammeter is 1A when
K is open.
6.
What will the ammeter reading be when k is closed?.
A.
0.2 A
B.
0.25 A
C.
1A
D.
4A
E.
5A
7.
If the ammeter near the 10Ω resistor is removed and then connected between X and Y, what will the ammeter reading
be when K is closed.
A.
0.20 A
B.
0.25 A
C.
1.00 A
D.
1.25 A
E.
5.00 A
8.
What is the e.m.f of the power supply?
A.
62.5 V
B.
50 V
C.
40 V
D.
12.5 V
E.
10.0 V
For Questions 9-10
In the circuit on the right, when only switch P is closed, the
voltmeter reading is 4 V. But when only switch Q is closed, the
voltmeter reading is 8 V.
R
2Ω
P
8Ω
Q
V
9.
The e.m.f. of the cell is
A.
4V
B.
6V
C.
8V
D.
10 V
E.
12 V
10.
The resistance of R is
A.
1Ω
B.
2Ω
C.
3Ω
D.
4Ω
E.
5Ω
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Mechanics I
1.
A
Which of the following paths is the displacement from P to Q?
Q
B
A.
B.
C.
D.
A
B
C
D
C
P
D
Q
2.
What is the displacement from P to Q?
A. 6 m
B. 8 m
C. 10 m
D. 14 m
Working steps :
6m
8m
P
3.
What is the displacement from P to Q if the diameter of each semi-circular path is 4m?
A.
B.
C.
D.
4.
6
7
8
9
A ticker-tape timer produced 50 dots in one second. What is the frequency of this timer?
A.
B.
C.
D.
6.
Q
P
How many tick-times are there in the following tape?
A.
B.
C.
D.
5.
12 m
24 m
12 π m
24 π m
49 Hz
50 Hz
51 Hz
From 49 to 51 Hz
Which of the following about a ticker-tape timer is possible?
A.
B.
C.
D.
Frequency of the tick-tpae timer
15 Hz
30 Hz
50 Hz
60 Hz
Time-interval for each tick-time
0.533 s
0.233 s
0.14 s
0.0167 s
S3 Physics
S3_____
7.
A photo of a multiple images of a moving object is taken with a stroboscope. There are 61 images
recorded in the photo within a 2-second time interval. What is the frequency of the stroboscope?
A.
B.
C.
D.
8.
10.
61 Hz
60 Hz
30.5 Hz
30 Hz
Working steps:
The following tape is produced by a trolley with a ticker-timer of 20 Hz. What is the average
speed within the first 5 cm ?
A.
B.
C.
D.
9.
Name ____________________________
Date : ____________________________
0.00714 m s-1
0.00833 m s-1
0.167 m s-1
0.0025 m s-1
5 cm
Working steps :
Which of the following is a distance-time graph?
A.
B.
C.
D.
Which objects, A,B,C or D, in the following v-t graph has the same acceleration as X?
(X)
(A)
(B)
(C)
(D)
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Mechanics II
Multiple choices : (For questions 1 to 6, hints are provided within the boxes and you have to fill them in. For
question 7 to 8, You must show your working steps in the spaces of these questions)
1.
A man takes 4 s to travel from point K to point M and then takes 2
s to walk from point M to point N as he cannot travel directly to N.
KMN is an equilateral triangle of side 6 m. What is the average
velocity from K to N ?
A.
B.
C.
D.
E.
2.
6m
The time needed to travelled from K to N is
_______ s
K
The average velocity fromK to N is
________ m s-1
800 m
400 m
2m
0.5 m
0.05 m
N
Since v = s/t, then s = ________
As v =______ m s-1, and t = ____ s,
Then s = _______ m
8 ms-1
50 ms-1
200 ms-1
800 ms-1
1000 ms-1
Since v = s/t,
As s =______m and t = _____ s
Then v = _________ m s-
The diagram below shows a series of photographs of a ball. They are taken with a stroboscope flashing at
a frequency of 15 Hz. What is the average speed of the ball?
<
A.
B.
C.
D.
E.
5.
6m
Ricky is standing on the platform of a KCR station. He notices that a train passes him in 4.0 s. The train is
200 m long. What is the average speed of the train?
A.
B.
C.
D.
E.
4.
Displacement from K to N is ______m
John travels from point A to point B at an average speed of 20 ms-1. The journey takes 40 seconds. What is
the distance between point A and point B ?
A.
B.
C.
D.
E.
3.
0.60 ms-1
1.00 ms-1
1.20 ms-1
1.25 ms-1
2.00 ms-1
M
2.00 ms-1
3.00 ms-1
3.75 ms-1
4.50 ms-1
15.0 ms-1
1m
>
Frequency is _______ Hz.
Time between two balls, t = _________ s
Total time interval between the first and last balls is __________ s
Average speed, v = _________ m s-
A bus is travelling at 10 metres per second. How far will the bus travel in 20 seconds?
A.
B.
C.
D.
E.
10 m
20 m
30 m
200 m
1200 m
Since v = s/t , s = (
)x( )
Thus s = __________ m
S3 Physics
S3_____
The graph shows how the speed of an object
changes with time. What is the distance travelled
in the first 4 seconds?
A.
B.
C.
D.
E.
8m
16 m
20 m
24 m
32 m
8
7
6
Speed/ms-1
6.
Name ____________________________
Date : ____________________________
Distance travelled is the area under the v-t
graph within that time-interval.
The area under the v-t graph from 0 to 4 s
is : _________________
5
4
3
2
1
0
0
1
2
3
4
5
Time/s
For Questions 7 and 8 : (Working steps needed)
The motion of a trolley is recorded by a
ticker-tape. The frequency of the ticker-tape
timer is 50 Hz. A ruler is placed against the
0 1
tape as shown in the figure.
cm
1
0
7.
3
4
6
7
8
9
10 11 12 13
0.01 s
0.1 s
0.5 s
5.0 s
10 s
There are _____ tick times within the 10 cm.
Each tick time : 1/f =
Total time taken is :
What is the average velocity of the trolley ?
A.
B.
C.
D.
E.
0.1 ms-1
0.2 ms-1
0.25 ms-1
0.5 ms-1
1 ms-1
v = s/t =
For Questions 9 and 10 : (HOT) (Working steps needed)
The distance travelled by the car in the first three
seconds is
24
20
Speed/ms-1
The graph shows the speed-time graph of a car in a
200 m race.
9.
5
What is the time taken for the trolley to move 10 cm ?
A.
B.
C.
D.
E.
8.
2
16
12
8
4
A.
B.
C.
D.
E.
10.
20 m
30 m
40 m
50 m
60 m
The total time taken for the car to complete the race is
A.
B.
C.
D.
E.
10.5 s
11.0 s
11.5 s
12.0 s
12.5 s
0
0
2
4
6
8
Time/s
10
12
14
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Mechanics III
1. John makes an observation of a stone which is thrown up by another student. The stone takes 0.5 second
to reach its highest position. After the stone leaves the student's hand and while it is travelling freely in
the air, it is subject to a downward acceleration of 10 m s-2.
a.
What will the velocity of the stone be when it reaches its highest position?
b.
What will the velocity of the stone be when it leaves the student's hand?
c.
What will the velocity of the stone be when it returns to where it left the student's hand?
d.
How long will the whole flight (飛航過程) of the stone be?
e.
Draw in the following graph paper a v-t graph of the stone from the moment it left the student's
hand to the moment it returned to the student's hand.
S3 Physics
S3_____
f.
Name ____________________________
Date : ____________________________
From the answers of a) to e), complete the followng description of the motion of an object being
thrown up.
After an object, e.g. a stone, is thrown upwards with an initial velocity of u m s-1, its upward
speed will gradually decrease with a downward acceleration of ___________ ms-2. When the
object reaches its highest position, its speed becomes _______ m s-1. Then its speed will gradually
_______________ downwards. When it returns to its initial level, its speed is also _____ m s-1 but
the direction of travelling is now ______________. Throughout the whole flight, the object is
subject to a downward acceleration of ________ m s-2 . The upward distance to the highest
position is ___________ to the downward distance back to the same level where it is thrown
upwards.
g.
Similarly, describe in complete sentences the motion of the following case.
A cannon (炮彈) is fired upward with an initial velocity of 20 m s-1.
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Mechanics IV
1.
When Michael Jordan jumps, he can hang in the air for 1 second, what is his jumping height ?
Then 2 a s = v2 – u2
2(-10)s = (0)2 – (5)2
s = -25/-20 = 1.25 m.
His jumping height = 1.25 m.
2.
Javier Sotomayor (蘇圖美亞) has a high jump world record of 2.45 metres in 1993. Whe he stood on the
athletic field, his center of mass was 1.2 m from the ground and when he was at his highest position, his
center of mass was 2 cm above the bar.
a.
What is his vertical speed when he was leaving the ground ?
The vertical distance that he can jump = 2.45 – 1.2 + 0.02 = 1.27 m
When he reaches the highest point, the speed (v) = 0 ms-1
2 a s = v2 – u2
2(-10)(1.27) = (0)2 – (u)2
u2 = 25.4
u = 5.04 ms-1
b.
How long did he travel in the air before he passed the bar ?
The time needed :
v=u+at
0 = 5.04 + (-10) t
t = 0.504 s
S3 Physics
S3_____
3.
Name ____________________________
Date : ____________________________
Belinda climbs up to a spring board of a swimming pool. She jumps up into the air, reaches the highest
point and then falls again.
a.
Belinda takes 0.7 s to reach the highest point of her jump. What is her speed when she leaves the
spring board?
b.
She takes another 1.6 s before entering the water. What is the height of the spring board above the
water?
c.
Find her speed when she enters the water.
d.
In the following graph, sketch the veolocity-time graph of her travel in air.
Graph paper for question d) and question e)
e.
Another diver who is twice as heavy as belinda jumps up with a higher speed. Sketch the possible
velocity-time graph of this diver in the graph of (d)
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Mechanics Experiment Worksheet 1
Objectives
To find out how the ticker-tape timer works
To measure the frequency of the ticker-tape timer
Apparatus
1 ticker-tape timer
1 power supply (12V a.c.)
1 stopwatch
1 roll of ticker-tape
Procedures
1. Connect the ticker-tape timer to the power supply as shown in the following figure. Turn on the timer
and examine how it works with the tape.
How does the ticker-tape timer work?
When the steel strip hits the carbon paper disc above the tape, _____ are produced on the tape.
2. Put a tape under the carbon paper disc. Slowly pull the tape away and turn on the ticker-tape timer for
about 5 seconds. Measure this time interval by a stopwatch.
Time read by the stopwatch is _________s
3. Count the dots on the tape and fill in the following information:
Number of dots within the time read by the stopwatch ___________ dots.
Average number of dots in one second are _________ dots
Therefore, Frequency of the timer = Number of dots in one second = _____________ Hz.
4. Find the time between one and the next dot, i.e. time for one tick or one tick time.
Time for one tick, or time interval between one and the next dot = _____________s.
Conclusion :
1. The ticker-tape timer works by __________ the carbon paper disc and producing
___________ on the tape.
2.
The Frequency of the timer is ________ Hz and one tick time (time for one tick) is ______s.
- End of Experiment 1 -
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Mechanics Experiment Worksheet 2
Objective
To obtain a distance-time graph from a trolley down a slope
Apparatus
1 ticker-tape timer
1 power supply (12V a.c.)
1 runway
1 roll of adhesive tape
Students’ tool : 1 pair of scissors and 1 glue stick
1 metre rule
1 trollley
1 roll of ticker-tape
Procedures
1. Set up the runway as the following figure shown. Adjust the slope of the runway until the trolley runs
freely down the runway with an increasing speed.
2. Connect the ticker-tape timer to the power supply and put a tape under the carbon paper disc with one
end stuck onto the trolley.
3. Give a push on the trolley when the ticker-tape timer is on.
4. Choose a dot on the tape obtained as the initial position and label it as O. Count the dots on the tape
begun from O with every 5-dot interval and cut them into pieces of paper tape. Label each piece of
paper tape in proper order such as 1, 2, 3,…… etc..
What is the time interval for each piece of paper tape? _________ s
5. According to teacher’s instructions, stick all pieces of tape on the paper to construct the graph of
distance against time, (i.e. distance-time graph). It is necessary to draw the x-axis and the y-axis with
clear divisions.
a. On the x-axis, draw a scale of 1 cm representing 0.1 second.
b. On the y-axis, 1 cm represents 1 cm.
c. Stick the tapes on to the graph in the ways specified by your teacher or in the way as shown in your
textbook P.____ (g).
d. Properly label graph.
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
6. Draw lines to connect the bottom-left corner to the top-right corner of all pieces of paper tape. The
joined line is called the graph of _________________ against __________. It can also be called
________________________________ graph.
7.
Describe the relationship between the time and the distance travelled.
- End of Experiment 2 -
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Mechanics Experiment Worksheet 3
Objectives
To obtain a velocity-time graph from a trolley down a slope
To describe the motion of a trolley in a graph
Apparatus
1 ticker-tape timer
1 power supply (12V a.c.)
1 runway
1 roll of adhesive tape
Students’ tool : 1 pair of scissors and 1 glue stick
1 metre rule
1 trollley
1 roll of ticker-tape
Procedures
1. Set up the runway as the following figure shown. Adjust the slope of the runway until the trolley runs
freely down the runway with an increasing speed.
2. Connect the ticker-tape timer to the power supply and put a tape under the carbon paper disc with one
end stuck onto the trolley.
3. Give a push on the trolley when the ticker-tape timer is on.
4. Choose a dot on the tape obtained as the initial position and label it as O. Count the dots on the tape
begun from O with every 5-dot interval and cut them into pieces of paper tape. Label each piece of
paper tape in proper order such as 1, 2, 3,…… etc..
What is the time interval for each piece of paper tape? _________
Are the distances/displacements travelled of all pieces of paper tape the same? ___________
Are the average velocities of all pieces of paper tape the same? __________
5. According to teacher’s instructions, stick all pieces of tape side by side on the paper to construct the
velocity-time graph. It is necessary to draw the x-axis and the y-axis with clear divisions as in P.69 (4).
S3 Physics
S3_____
6. Properly label the graph.
Velocity m/s
Name ____________________________
Date : ____________________________
The graph of velocity against time (velocity – time graph)
1.5
1.0
0.5
0
0
0.5
1.0
1.5 Time /s
7. Describe the motion of the trolley in the graph.
The ___________________ of the trolley is ____________________________________
(increasing 增加, decreasing 減少, constant 固定,不變)
- End of Experiment 3 -
S3 Physics
S3_____
Objective:
Name ____________________________
Date : ____________________________
Mechanics Experiment Worksheet 4
1. To experience the existence of force and the proof of its existence.
2. To differentiate two types of forces.
Apparatus :
Newton Balance
String
A pair of Scissors
Magnet
Experiment 1
Procedures:
1. Tie a string to a Newton balance.
2. Student A holds the Newton balance and student B pulls the string slightly.
3. Another student, C, reads the reading of the Newton balance.
4. Repeat the above steps from procedures 2 to 3 with different pulling forces. Write the readings in the
following boxes.
a.
b.
c.
d.
5. Will there be any reading in the Newton balance if student B does not pull the string.
6. Conclusion : Newton balance can/cannot indicate whether a force is existed in the string.
Experiment 2
Procedures:
1. Tie a string to a Newton balance.
2. Student A holds the Newton balance and student B pulls the string slightly.
3. Another student, C, reads the reading of the Newton balance.
4. Now, student C cuts the string and observes if there is any change in the reading in the Newton
Balance and how student B reacts.
5. Repeat the above steps from procedures 2 to 3 with different pulling forces. Write the readings in the
following boxes.
a.
b.
c.
d.
Before the string is cut
After the string is cut
6. Is there any reading in the Newton balance immediately after the string is cut?
No.
Did student B move immediately after the string is cut?
Yes.
7. Conclusion : After the string is cut, student B moves backward, but there is not a force existed or
indicated/because there is a force existed.
Experiment 3:
Procedures :
1. Student A and student B each holds a magnet as shown in the diagram.
2. Now, student B moves his/her magnet close to student A’s magnet.
3. Is there any force existed?_____________________________________
4. Now, student B reverses his/her magnet and repeats the procedure 2.
5. Is there any force existed? ____________________________________
How is this force different from that in procedure 3.
One is attractive and the other repulsive./ One is attraction and the other
repulsion./ One attracts each other and the other repels.
6. Are these forces in direct or indirect contact? _________________________
Are they separated at a distance?________________________________________
Conclusion :
There are two types of forces, i.e. force in
-- End --
and force at a
.
S3 Physics
S3_____
Name ____________________________
Date : ____________________________
Current Electricity experiment worksheet
Objective : To verify the ohm’s law
Apparatus:
1 power supply
1 circuit board
1 resistor (red)
several connecting wires
1 voltmeter
1 switch
1 ammeter
Your power supply consists of 4 electric cells. In this experiment, you are to measure the relationship
between the current passing through and the potential difference across a resistor.
1.
Connect a red resistor, an ammeter, a switch and a power supply (4
cells) in series as shown in Figure 1.
Figure 1
2.
Close the switch and measure the current shown in the ammeter,
record the reading in Table 1.
3.
Keep the switch closed. Use the voltmeter to measure the potential
difference across the red resistor as shown in the figure 2. Record
the reading in Table 1.
Figure 2
4.
Repeat steps 1 to 3 with different numbers of electric cells in the power supply. Also record the results in
Table 1.
Test No.
Reading of Ammeter Reading of Voltmeter
(Current, A)
(p.d., V)
Remark
1
One cell
2
Two cells
3
Three cells
4
Four cells
Table 1
S3 Physics
S3_____
5.
Name ____________________________
Date : ____________________________
In the graph below , plot the graph of V against I.
The proportional constant (resistance) of the resistor is : ___________ Ω
Ohm’s law states that the p.d. across a conductor is ___________ proportional to the current through it,
provided that the ___________ and other physical conditions are constant.
The ratio of p.d./current is the resistance of the conductor. It is measured in __________________.