Which of these colours in the visible spectrum has the longest wavelength?
คำตอบ
(A)
Red
2
The power of a lens in diopters is
คำตอบ
(B)
\(\frac{1}{\text{f}}\)
3
A man moves 6.0m East and then 10.0m N30ºE. How far is he from his starting point?
คำตอบ
(C)
14.0m
4
The density of water is 1g/cm\(^3\) while that of ice is 0.9g/cm\(^3\). Calculate the change in volume when 90g of ice is completely melted.
คำตอบ
(D)
10cm\(^3\)
5
The graphical representation of the pressure law is always a straight line passing through the origin, only if the temperature scale is
คำตอบ
(D)
thermodynamic
6
According to the kinetic theory of gases, the pressure exerted by a gas on the walls equals.
คำตอบ
(D)
Rate of change of momentum imparted to the walls per second per unit area.
7
Which of the following is not true about a wave in a plucked string?
คำตอบ
(D)
It is longitudinal
8
The emf of a cell is the potential difference across its terminals when it is in
คำตอบ
(C)
open circuit
9
The thermometric property of mercury is best on the change in
คำตอบ
(B)
volume with temperature
10
Some of the features of the human eye that greatly help to refract light entering the eyes are
คำตอบ
(A)
cornea and lens
11
When both the object and its image move together in the same direction relative to the observer, then there is
คำตอบ
(A)
no parallax error
12
The diagram above shows a magnetic field due to a
คำตอบ
(C)
current-carrying straight conductor
13
I. The colour of light depends on its frequency II. When white light is dispersed by a triangular prism, yellow is deviated more than green III. Rainbows are formed when rains fall heavily. Which of the above statements is/are correct about dispersion and colours?
คำตอบ
(B)
I only
14
A Force 18 N pulls a 40 kg mass on a horizontal floor at 0.3 ms\(^{-2}\). Find the coefficient of friction.
คำตอบ
(B)
0.015
15
A 500W electric oven plugged into a 220 V source will consume an electric current of
คำตอบ
(B)
2.27A
16
A hydraulic press consists of two cylinders of cross-sectional radius r\(_1\) and r\(_2\). If a force of 200N applied to the smaller piston (r\(_1\)), causes a force of 3200N to be transmitted onto the larger piston (r\(_2\)). The ratio r\(_1\): r\(_2\) is?
คำตอบ
(A)
1:4
17
The gravitational pull between two bodies is 20N. Find the gravitational pull when their distance of separation is doubled.
คำตอบ
(B)
5N
18
The volume of a 1 cm\(^3\) metal ball increases by 0.0018 cm\(^3\) when heated through temperature θ. If the linear expansivity of the ball is 2.0 x 10\(^{-5} K^{-1}\), find θ.
คำตอบ
(C)
30°C
19
For a gas, which pair of variables is inversely proportional to each other (provided other conditions are constant), where P = pressure, T= temperature, V= volume, and n= number of molecules?
คำตอบ
(B)
P, V
20
A boy uses a single string pulley system to lift a mass of 20kg moving with a velocity of 5ms\(^{-1}\). What is the power developed by the boy if g = 10ms\(^{-2}\)?
คำตอบ
(B)
1000W
21
Without considering the containing vessel, what mass of boiled water can raise the temperature of 8 kg of water from 25°C to 60°C when mixed in a heat-proof container?
คำตอบ
(B)
7kg
22
Which of the following has the least thermal conductivity?
คำตอบ
(A)
air
23
5400kJ of heat energy was lost when some amount of steam condensed to water for drinking purposes at 15º C. What is the quantity of water collected? [L\(_f \) = 2.26 × 10\(^6\) Jkg\(^{-1}\), c\(_w\) = 4200 Jkg\(^{-1}K^{-1}\)]
คำตอบ
(D)
2.06 kg
24
Charge carriers in doped semiconductors are
คำตอบ
(D)
electrons and holes
25
If the critical angle for a glass–air boundary is 45º, what is the refractive index of the glass?
คำตอบ
(A)
\(\sqrt{2}\)
26
The volume of a fixed mass of gas at 0º C is 200 m\(^3\). What is its volume at 273º C at constant pressure?
คำตอบ
(B)
400 m\(^3\)
27
The device that operates using the magnetic effect of electric current is
คำตอบ
(C)
Electric bell
28
Calculate the decay constant of a radioactive isotope of half-life 138.5 s.
คำตอบ
(A)
5.0 × 10\(^{-3}\) s\(^{-1}\)
29
How long will it take to heat 4 kg of water from 30ºC to 65ºC using an electric kettle taking 5 A from a 240 V supply?
(Specific heat capacity of water = 4200 J kg\(^{-1}\) K\(^{-1}\))
คำตอบ
(C)
490 s
30
The figure shows a uniform metre rule of weight 100 N balanced by a knife edge at the 10 cm mark and a cord attached at the 85 cm mark. What is the tension in the string?
คำตอบ
(B)
53.33 N
31
What form of energy is present in the food we eat?
คำตอบ
(D)
Chemical
32
What magnitude of electric current can store 2.5 J of energy in a 3 H induction coil?
คำตอบ
(A)
1.29 A
33
A machine has an efficiency of 80%. If the input work is 200J, the output work is?
คำตอบ
(B)
160J
34
A wooden block of relative density 0.4 floats in a liquid of density 1600 kg m\(^{-3}\). What fraction of its volume is immersed?
คำตอบ
(C)
0.25
35
Lining the walls of an auditorium with perforated materials reduces
คำตอบ
(A)
reverberation
36
If an object sinks in water, it means that
คำตอบ
(A)
Its density is greater than that of water
37
A well-lagged thin metal rod of length 0.2 m has a temperature gradient of 416 K m\(^{-1}\). If one end is at 233º C, what is the temperature at the other end?
คำตอบ
(D)
316.28°C
38
The movement of particles in liquids and gases is referred to as
คำตอบ
(C)
Brownian motion
39
What mass of silver is deposited during electrolysis when a current of 0.8 A flows for 25 minutes?
คำตอบ
(D)
1.34g
40
The thermal capacity of a body depends on one of the following
คำตอบ
(C)
Nature and mass
41
What is the pressure exerted by 4.5m\(^3\) of gas at 17ºC in a cylinder if the number of moles is 8.3 moles? (R = 8.31 JK\(^{-1}\)mol\(^{-1}\))
คำตอบ
(D)
4445Pa
42
The tangential force acting on an object that opposes it from sliding freely on the adjacent surface is called
คำตอบ
(C)
Frictional force
43
The point where no magnetic effect is felt around a magnet is
คำตอบ
(D)
Neutral point
44
If the specific gravity of a liquid is 0.76, calculate its density((\(\rho_w\) = 1000Kgm\(^{-3}\))
คำตอบ
(A)
760Kgm\(^{-3}\)
45
Copper of 0.2g and silver of 1.2g are deposited when current is passed through copper and silver voltameter. Calculate the electrochemical equivalent, Z of silver if that of copper is 0.00028gC\(^{-1}\)
คำตอบ
(A)
1.68 x 10\(^{-3}\)gC\(^{-1}\)
46
Calculate the heat capacity of a material that absorbs 48KJ of heat at a differential temperature of 53ºC
คำตอบ
(C)
905.7JK\(^{-1}\)
47
Which of the following electromagnetic spectra has the shortest wavelength?
คำตอบ
(B)
X - rays
48
A wire of radius 0.3cm is used to lift a block of 1.5kg. Calculate the stress introduced into the wire [ take g = 10m/s\(^2\)]
คำตอบ
(C)
53 x 10\(^4\)Nm\(^{-2}\)
49
The quantity of heat required to convert 5kg of ice at its melting point to water without a change of temperature is
คำตอบ
(D)
Latent heat of fusion.
50
Which of the following is better for measuring a very small resistance?
คำตอบ
(B)
Wheatstone bridge
51
In an A.C circuit, the instantaneous current is 7A. What is the root mean square(r.m.s) value of the current I\(_{r.m.s}\)
คำตอบ
(A)
5A
52
Calculate the depth of a swimming pool if the apparent depth is 10cm(refractive index of water is 1.33)
คำตอบ
(C)
13.3cm
53
A 5 \(\mu\) positively charged particle is moving at 45º to the direction of magnetic field with 3 x 10\(^4\)m/s speed. If it experiences a force of 6N, what is the value of the flux density of the field?
คำตอบ
(D)
56.57T
54
The dimensional symbol of tension in a string is expressed as
คำตอบ
(D)
M L T\(^{-2}\)
55
From the above circuit, calculate the impedance ((\(\pi\) = \(\frac{22}{7}\), f = 50Hz)
คำตอบ
(B)
163.5\(\Omega\)
56
What pressure would a 5000N weight of water exert at the bottom of a reservoir containing it if its length and breadth are 10m and 5m, respectively
คำตอบ
(C)
100Pa
57
Standing waves are produced by
คำตอบ
(D)
waves that reflect off a boundary and interfere with themselves
58
From the above figure, a uniform meter rule is suspended by two cords from a height. Calculate T?
คำตอบ
(C)
19.24N
59
From the diagram above, the sine of the angle of refraction in glass is
คำตอบ
(B)
0.3
60
What happens to the speed of sound in air when the pressure increases at a constant temperature
คำตอบ
(A)
Unchanged
61
The operation of a photovoltaic cell is possible by the action of
คำตอบ
(A)
Semi-conductor
62
A concave mirror of focal length 20cm produces an erect image that is four times the object, the object distance from the mirror is
คำตอบ
(A)
less than 20cm
63
The resultant of the force shown above is
คำตอบ
(B)
5.00N
64
A circular parallel plate capacitor with radius 6cm is separated by 0.12cm. Calculate the capacitance of the capacitor [\(\pi\) = 3.142, ε\(_0\) = 8.85 x 10\(^{-12}\)Nm\(^2\)C\(^2\)]
คำตอบ
(C)
8.3 x 10\(^{-11}\)F
65
Calculate the specific heat capacity of a metal rod of mass 0.025kg whose temperature was raised by 15ºC when 1000J of heat energy was added to the rod(assuming the heat loss to the surrounding is negligible)
คำตอบ
(D)
2666.7JKg\(^{-1}\)K\(^{-1}\)
66
The speed of sound in air is 60 m/s. How far from the centre of a storm is an observer who hears a thunder clap 4s after the flash of the lightning?
คำตอบ
(D)
240m
67
Which of the following thermometer types best responds to a change in temperature
คำตอบ
(B)
Resistance thermometer
68
A 25cm long pinhole camera produces a one-fifth of an object's size. Calculate the object distance
คำตอบ
(D)
1.25m
69
What is the mass of a particle with speed 2.7 x 10\(^8\)m/s and wavelength 4.0 x 10\(^{-7}\)mm? (h = 6.63 x 10\(^{-34}\)Js)
คำตอบ
(B)
6.1 x x 10\(^{-31}\)Kg
70
At what distance from a 1.2 x 10\(^{-7}\)C point charge will the electric field intensity be equal to 4.8 x 10\(^{-4}\)NC\(^{-1}\) [ Take \(\frac{1}{4\pi ε_0}\) = 9.0 x 10\(^9\)]
คำตอบ
(B)
3.0Km
71
Using the oscillating simple pendulum above, the maximum kinetic energy is obtained at
คำตอบ
(A)
Q
72
A collection of condensed suspended dust particles in the air constitute
คำตอบ
(B)
fog
73
A body is moving initially at 4m/s. If it's impulse after accelerating at 5m/s\(^2\) for 2s is 60Kgms\(^{-1}\). What is its mass?
คำตอบ
(C)
6Kg
74
A bore made in an aluminium block at 34ºC is 3.48cm\(^3\). What is the new bore when the temperature was raised to 340ºC [α\(_a\) = 24 x 10\(^{-6}\)K\(^{-1}\)]
คำตอบ
(B)
3.83cm\(^3\)
75
A short-sighted person's far point is 95cm. The defect can be corrected using
คำตอบ
(C)
Diverging lens of focal length 95cm
76
A refrigerator uses 150W. If it is kept on for 336 hours nonstop. What is the energy consumed in Kwh?
คำตอบ
(C)
50.40Kwh
77
The commonly used materials for shielding or screening magnetism is
คำตอบ
(C)
Soft iron
78
One of the following is not a radiation detector
คำตอบ
(A)
Electrophorus
79
What is the electrolyte used in wet Leclanche cell
คำตอบ
(C)
Ammonium chloride
80
In electromagnetic induction, the generated electricity is actually a voltage called
คำตอบ
(A)
Induced emf
81
Which of the following is a basic Unit?
คำตอบ
(D)
Ampere
82
The acceleration of the body given above ( upthrust = 10N)
คำตอบ
(C)
7.5m/s\(^2\)
83
The distance between two successive trough points of a wave is
คำตอบ
(B)
a wavelength
84
What colour has the lowest frequency in the spectrum of white light?
คำตอบ
(A)
Red
85
If 10 objects, tinsels are placed between the mirror of a Kaleidoscope with an inclination of 30º, how many images are formed?
คำตอบ
(A)
110
86
When capacitors are connected in series across a potential difference, there is a loss in their stored energy because:
คำตอบ
(D)
decrease in the overall capacitance of the capacitors
87
The diagram above is a vector field. Determine the magnitude of the vector
คำตอบ
(C)
2\(\sqrt{2}\)NC\(^{-1}\)
88
The focal length of the natural eye lens is variable due to the action of the
คำตอบ
(B)
Ciliary muscle
89
An annular eclipse is formed when
คำตอบ
(A)
The sun, moon, and earth comes in straight line
90
If a positively charged rod is brought close to the cap in the diagram above, the divergence
คำตอบ
(B)
Increases
91
If the weight of an object on the Earth's surface is 2.5 x 10\(^3\)N, what is its weight on the moon's surface if the gravitational force of the moon is one-sixth of the Earth's(g = 10m/s\(^{-2}\))
คำตอบ
(B)
416.67N
92
A boat or airplane has a pointed front or head. This is to
คำตอบ
(A)
Reduce the friction of fluid
93
A gas is cooled at a constant pressure from 57ºC was observed to shrink one-fifth (1\5) of its original volume of 2.00cm\(^3\). Find its new temperature
คำตอบ
(B)
-207\(^0\)C
94
The gravitational force between two masses, P and Q, is 10N, find the new value of the force if both masses are doubled
คำตอบ
(A)
40.0N
95
If the length of a simple pendulum is 120cm, calculate its frequency [\(\pi\) = \(\frac{22}{7}\) g = 10ms\(^{-2}\)]
คำตอบ
(D)
0.5Hz
96
From the above graph, what is the distance covered in the last stage of the motion?
คำตอบ
(B)
28m
97
Assuming E\(_1\), E\(_2\), and E\(_3\), are equal, then the total e.m.f of the arrangement will be given by
คำตอบ
(D)
E = \(E_1\) = \(E_2\) = \(E_3\)
98
Given that SQ = 10cm and SR = 6cm, the refractive index of the block of glass shown in the above figure is
คำตอบ
(A)
1.67
99
Water waves and light waves differ generally in their
คำตอบ
(D)
medium of propagation
100
A method of demagnetization is
คำตอบ
(C)
heating a magnetic bar red hot and allowed to cool e-w direction
