What is the least possible error in using a rule graduated in centimeters?
Απάντηση
(A)
0.1cm
2
Which of the following affects the period of a simple pendulum? i. mass of the pendulum bob. ii. length of the pendulum. iii. acceleration due to gravity.
Απάντηση
(B)
ii and iii only
3
A boy sits in a train moving with uniform speed on a straight track. If from his outstretched palm he gently tosses his coin upwards, the coin will fall
Απάντηση
(D)
into his palm
4
A body starts from rest and moves with a uniform acceleration of 6 ms \(^{-2}\). What distance does it cover in the third seconds
Απάντηση
(A)
15m
5
A stone, Q is thrown with velocity U at an angle of 75o to the horizontal. Another stone R is thrown with the same velocity U but with an angle of 15o to the horizontal. The ranges covered by the stones will be
Απάντηση
(C)
the same for Q and R
6
A man weight 800N climbs up a stairs to height of 15m in 12.5s. What is the man''s average power output?
Απάντηση
(C)
960W
7
A machine requires 1000J of work to raise a load of 500N through a vertical distance of 1.5m. Calculate the efficiency of the
Απάντηση
(B)
75%
8
In an experiment to determine Young's Modulus for a wire, several loads are attached to the wire and the corresponding extension measured. The tensile stress in each case depends on the
Απάντηση
(B)
load and the radius of the wire
9
If a plastic sphere floats in water (density = 1000kgm3) with 0.5 of its volume submerged, and floats in oil with 0.4 of its volume submerged the density of the oil is
Απάντηση
(C)
1250kgm3
10
A platinum resistance thermometer wire has a resistance of 5 ohms at 0oC and 5.5 ohms at 100oC. Calculate the temperature of the wire when the resistance is 5.2 ohms
Απάντηση
(C)
40oC
11
A bridge made of steel is 600m long. What is the daily variation in its length if the night-time and daytime temperatures are 10°C and 35°C respectively. The linear expansivity of steel is 0.000012C\(^{-1}\).
Απάντηση
(C)
18.00cm
12
One of the most important applications of bi-metallic strip is found in the construction of
Απάντηση
(A)
a thermostat
13
At constant pressure, the density of a fixed mass of gas is
Απάντηση
(C)
inversely proportional to its temperature
14
How much heat is absorbed when a block of copper of mass 0.05kg and specific heat capacity 390Jkg-1K-1 is heated from 20oC to 70oC?
Απάντηση
(B)
9.75 x 102J
15
A block of ice floats on water inside a container. If the block of ice gets completely melted, the level of water in the container will
Απάντηση
(B)
remain the same
16
The space between the double glass walls of a thermos flask is evacuated space are silvered. The residual source of heat loss takes place by
Απάντηση
(C)
conduction through the stopper and the glass
17
The equation of a wave is y = 0.005 sin[x(0.5X - 200t)] where x and y are in meters and t is in seconds. What is the velocity of the wave?
Απάντηση
(B)
400ms-1
18
Which of the following characteristics of a wave is used in the measurement of the depth of the sea?
Απάντηση
(D)
reflection
19
A note is the octave of another note if it has
Απάντηση
(A)
a frequency twice that of the first note
20
What is the frequency of the sound made by a siren having a disc with 32 holes and making 25 revolution per seconds?
Απάντηση
(C)
800Hz
21
Which of the following properties make the convex mirror useful as a driving mirror? i. the image is real. ii. the image is erect. iii. it has a wide field of view. iv. the image is magnified.
Απάντηση
(C)
ii and iii
22
When an object is placed very close to the pole of a concave mirror, the virtual image obtained is
Απάντηση
(D)
enlarged and upright
23
A concave mirror has a radius of curvature of 36cm. At what distance from the mirror should an object be placed to give a real image three times the size of the object?
Απάντηση
(B)
24cm
24
Which of the following statements is CORRECT about a long-sighted boy who does not put on glasses?
Απάντηση
(D)
Parallel rays of light are focused behind his retina
25
The speed of light in air is 3 x 10\(^8\)ms\(^{-1}\). What is the speed in glass with a refractive index of 1.50?
Απάντηση
(C)
2.0 x 108ms-1
26
If the refractive index of a medium in air is 2.0, what is the critical angle for this medium?
Απάντηση
(A)
30o
27
Which of the following arrangements of the components of electromagnetic spectrum is in ascending order of wavelengths?
The angle between the direction of the earth's magnetic field and the horizontal is called the
Απάντηση
(D)
angle of dip
29
Calculate the force acting on an electron of charge 1.6 x 10-19C placed in an electric field of intensity 108Vm-1
Απάντηση
(A)
1.6 x 10-11N
30
When an ebolite rod is rubbed with fur, it has
Απάντηση
(B)
a negative charge
31
Which of the following factors has no effect on the e.m.f. of a primary cell?
Απάντηση
(B)
size of the cell
32
A wire of length 15m made of a material of resistivity 1.8 x 10-6\(\Omega\)m has a resistance of 0.27\(\Omega\). Determine the area of the wire
Απάντηση
(B)
1.0 x 10-4m2
33
A 5-v battery is connected across the plates of a 2.0\(\mu\)F uncharged parallel plate capacitor. The charge on the capacitor after a long time is
Απάντηση
(B)
10.0\(\mu\)C
34
Which of the following apparatus will require the smallest fuse rating for its protection?
Απάντηση
(A)
60W, 240V
35
The heat produced in a conductor carrying an electric current is
Απάντηση
(D)
directly proportional to the square of the current, the resistance and the time
36
The maximum permissible current through a galvanometer G of internal resistance 10\(\Omega\) is 0.05A. A resistance R is used to convert G into a voltmeter with a maximum reading of 100V. Find the value of R and how it is connected to G
Απάντηση
(C)
1990 ohms in series
37
In alternating current theory, the units of impedance, r.m.s. voltage and resonance frequency are respectively equal to
Απάντηση
(B)
ohms, volt and hertz
38
In A.C circuit theory, the root means square (r.m.s) current, Irms and the peak (maximum)current Io are related by
Απάντηση
(B)
Irms = \(\frac{I_o}{\sqrt{2}}\)
39
The threshold of frequency for photoelectric effect depends on the
Απάντηση
(C)
material of the photocathode
40
After three half lifes, the fraction of a radioactive material that has decayed is
Απάντηση
(D)
\(\frac{7}{8}\)
41
\(^{27}_{13}Al\) + \(^{1}_{0}n\) \(\Rightarrow\) \(^{24}_{11}Na\) + X
Απάντηση
(D)
an alpha particle
42
A uniform light rod is kept in horizontal equilibrium under the influence of fore forces as shown above, which of the following equations correctly represents the condition of equilibrium for the rod
Απάντηση
(D)
F1a + F2b - F3c - F4d = 0
43
In the diagram above, the hanging mass \(m_2\) is adjusted until \(m_1\) is on the verge of sliding. The coefficient of static friction between the mass \(m_1\) and the table is
Απάντηση
(C)
m2/m1
44
The fig above shows the heights of two liquids X and Y when some air is sucked out of the apparatus through the pump P. The diameter of the table in X is twice That of the Tube In Y. What is the relative density of the liquid X with respect to liquid Y
Απάντηση
(C)
3
45
The diagram above represents the field pattern obtained by bringing the poles of two magnets together.The poles must be
