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Fizik Kertas 2 OGOS 2008 2 ½ Jam SEKOLAH MENENGAH TEKNIK SEJINGKAT KUCHING SARAWAK PEPERIKSAAN PERTENGAHAN TAHUN 2012 FORM 4 FIZIK KERTAS 2 Dua jam tiga puluh minit JANGAN BUKA KERTAS SOALAN INI SEHINGGA DIBERITAHU. Kegunaan Pemeriksa 1. Tulis nama Untuk dan tingkatan anda pada ruang yang disediakan. Bahagian Soalan Markah 2. Kertas soalan ini adalah dalam dwibahasa. 1

2 3. Calon dibenarkan menjawab keseluruhan atau sebahagian 3 Inggeris atau bahasa Melayu. soalan sama ada dalam bahasa 4

A 5 4. Jawapan kepada Bahagian A hendaklah ditulis dalam ruang 6 soalan. yang disediakan dalam kertas 7 5. Rajah tidak dilukis mengikut skala kecuali dinyatakan.

6. Markah maksimum yang diperuntukkan ditunjukkan dalam 1 kurungan pada hujung tiap-tiap soalan atau

B

2 saintifik diprogramkan adalah dibenarkan.

7. Penggunaan

kalkulator C

yang

Jumlah Besar

Prepared by : ( En. Sakawi Bin Len ) Guru Fizik

Checked by : ( En. Lemon Ak Dabut ) Head of Physics Panel

Confirmed by : ( Mdm Loi Hua King ) Head of Sc & Math Department

tidak

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The following information may be useful. The symbols have their usual meaning. Maklumat berikut mungkin berfaedah. Simbol-simbol mempunyai makna yang biasa.

v−u t v2 = u2 + 2as 1 s = ut + at2 2 Momentum = mv

1. 1.

a=

2. 3. 4.

F = ma

5.

Kinetic energy = ½ mv2

6.

Gravitational potential energy = mgh

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3 Section A [60 marks] Answer all questions

1. Diagram 1 shows the graph of velocity against time for the motion of a car. Rajah 1 menunjukkan graf halaju lawan masa untuk gerakan sebuah kereta.

Diagram 1 Rajah 1

(a)

State the physical quantity represented by Nyatakan kuantiti fizik yang diwakili oleh

(i)

the gradient of the graph. kecerunan graf

(ii)

……………………………………………………………………….. [1 mark] the area under the graph. luas di bawah graf

…………………………………………………………………….. [1 mark] (b)

Complete the table below. Lengkapkan jadual berikut.

Section of the graph

Type of motion of the car

Bahagian graf

Jenis gerakan kereta

OA AB [2 marks]

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Figure (a) below shows a micrometer screw gauge.

(a) (i)

Name the parts labelled U, V and W ____________________________________________________________________ ____________________________________________________________________ _________________________________________________________________ ( 3 marks )

(ii)

What is the accuracy of this instrument? ___________________________________________________________________ ( 1 mark ) (iii) What is the use of the part labeled W? ___________________________________________________________________ ( 1 mark ) (b) Fig. (b) shows the scales when the micrometer is fully closed while Fig. (c) shows the scales when a small ball bearing is placed between the anvil and the spindle.

(i) (ii)

What is the zero error of the micrometer screw gauge? ___________________________________________________________________ ( 1 mark ) Determine the diameter of the ball bearing ( 2 marks )

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The figure below shows a ticker tape chart obtained from the motion of a trolley down an inclined plane. Each strip of ticker tape contains 10 ticks. The ticker timer makes 50 ticks per second.

(a) What type of power supply is used to run the tick _______________________________________________________________________ ( 1 mark ) (b) What is the time interval for 1 tick on the ticker tape? _______________________________________________________________________ ( 1 mark ) (c) What is the type of motion shown by the trolley? ________________________________________________________________________ ( 1 mark ) (d) What is the average velocity shown by the first strip of ticker tape?

( 2 marks ) (e) Calculate the acceleration of the trolley.

( 2 marks )

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6

Ahmad cycles to school everyday. The graph below shows a typical velocity-time graph of Ahmad's journey to school.

(a) During which part of the journey is Ahmad : (i) (ii)

Accelerating :…………. Decelerating :…………

( 2 marks ) (b) For how long is Ahmad cycling with constant velocity? _______________________________________________________________________ ( 1 mark ) (c) How far is Ahmad's school form his house?

( 2 marks )

(d) What is Ahmad's average velocity for the whole journey?

( 2 marks )

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5. A car moves with an average speed of 75 km h-1 from town P to town Q in 2 hours as shown in Figure 1. By using this information, you may calculate the distance between the two towns. P Q

Figure 1 (a) (i) Based on the statements given, state two basic quantities and their respective SI units. ……………………………………………………………………… [ 1 mark ] (ii) State a derived quantity and its SI unit. ………………………………………………………………………[ 1 mark ] (b) Convert the value

1 . m to standard form. 5 x 10-3 [ 3 marks ]

(c) Complete Table 1 by writing the value of each given prefix.

Table 1 [ 4 marks ] (d) Power is defined as the rate of change of work done. Derive the unit for power in terms of its basic units. [5 marks ] (e) Calculate the volume of a wooden block with dimension of 7 cm, 5 cm breadth and 12 cm height in m3 and convert its value in standard form.

[ 5 marks ]

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6.

ceiling

Tin

water P

b)

N

Q (i)

a)

M

 hand

R

Diagram 2.1

(ii)

Diagram 2.1(i) shows tin P that is empty and tin Q that is filled with water. A student find difficult to pushed tin Q. Write the inference about the observation. ………………………………………………………………………………… [ 2 marks ] Diagram 2.1(ii) shows a tin being released from the different positions M and N. The hand of a student at position R needs greater force to stop the motion of the tin falling from position M. Explain this observation. ………………………………………………………………………………… ……

c)

d)

………………………………………………………………………………… [ 2 marks ] Based on the observation (i) and (ii), state two factors that affect the magnitude of the momentum of the object. ………………………………………………………………………………… [ 2 marks ] If water flows out from a hole at the bottom of the tin Q, how would the inertia of Tin Q depends on time ? ……………………………………………………………………………… [ 2 marks ]

7

Diagram 1.1 shows an oscillating pendulum.

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9 Rajah 1.1 menunjukkan ayunan sebuah bandul.

Diagram 1.1 (a) Based on Diagram 1.1, choose the correct path for one complete oscillation. Tick (√) the correct answer in the box provided. Berdasarkan Rajah 1.1, pilih lintasan yang betul untuk satu ayunan lengkap. Tandakan (√) jawapan yang betul dalam petak yang disediakan.

P

Q

P

Q

R

P

Q

R

Q

P [ 2 mark ]

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10 (b) The stop watch in Diagram 1.2 shows the time taken for the pendulum to make 20 complete oscillations. Jam randik dalam Rajah 1.2 menunjukkan masa yang diambil untuk bandul itu membuat 20 ayunan lengkap.

Based on Diagram 1.2, state Berdasarkan Rajah 1.2, nyatakan (i) the smallest division of the stop watch. Senggatan terkecil bagi jam randik itu. __________________________________________________________________ [ 2 mark ] (ii) the time taken for 20 complete oscillations. Masa yang diambil untuk 20 ayunan lengkap. _______________________________________________________________ [ 2 mark ] ( c ) What is the type of physical quantity for time? Tick (√) the correct answer in box provided. Apakah kuantiti fizik bagi masa? Tandakan (√) jawapan yang betul dalam petak yang disediakan. Scalar quantity Kuantiti skalar Vector quantity

[ 1 mark ]

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Section B [ 20 marks ]

1.

(i)

(ii)

Diagram 1.1 Diagram 1.1(i) shows the condition of a car moving at high velocity when it suddenly crashes into a treel. Diagram 1.1(ii) shows a tennis ball hit with racquet by a player. a) (i) What is the meaning of momentum? [ 1 mark] (ii)

b) c)

Based on the observations of Diagram (i) and (ii), compare the characteristics of car when it crashes into the tree and the tennis ball when it is hit with a racquet. Hence, relate these characteristics to clarify a physics concept, and name this concept. [ 5 marks ] Explain why a tennis player uses a taut racquet when playing. [ 4 marks ] In launching a rocket, a few technical problems have to be overcome before the rocket can move upright to the sky. By using appropriate physics concepts,

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12 describe the design of a rocket and the launch techniques that can launch the rocket upright. [ 10 marks]

Section C [ 20 marks ] 2.

Properties Brand

A B C D

Reaction time / s

Mass / kg

0.3 0.5 0.2 0.6

1.5 1.8 0.9 2.5

Engine thrust force / N 10.0 12.5 6.5 16.0

Resistance force /N 4.0 2.4 2.2 6.5

In a radio-controlled car racing competition, 4 mini-cars branded A, B, C and D took part. The information of the 4 cars is given in the table above. Details of the above information are given as below; Reaction time - Duration between the moment the radio-controlled is switched on and the moment the car starts moving. Resistance - Average value of opposing forces includes the friction between wheels and track, and air resistance. (a) What is the meaning of acceleration? [ 1 mark ] (b)

(c)

(c)

Draw a graph of velocity against time that shows a car moving initially with constant acceleration, then moving with constant velocity and followed by constant deceleration until it stops. [ 4 marks ] Explain the suitability of the properties in the above table in constructing a radio-controlled car racing purpose. Hence, determine which brand of car will win the 50-metre race. [ 10 marks ] If Car B in the above table is moved up the plane at the angle of 30o to the horizon, (i) Show that the car is able to move up the plane. (ii) Determine the acceleration of the car. [ 5 marks ]

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END OF QUESTIONS

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