Problem 1
Which one of the following statements is INCORRECT?
(A) If the net force on a body is zero, its velocity is constant or zero
(B) If the net force on a body is zero, its acceleration is constant and
(C) If the velocity of a body is constant, its acceleration is zero
(D) A body may have a varying velocity yet a constant speed
Problem 2
Two forces each of magnitude (P) act on a body placed at a point (O) as shown. The force necessary to keep the body at rest is of magnitude.
(A) P along +X axis
(B) P along - X axis
(C) 2 P along +X axis
(D) P/2 along - X axis
Problem 3
Two spheres having masses 10 g and 25 g are projected horizontally from the same height with velocities \(v_1\) and \(v_2\) and they fall to the ground in time intervals \(t_1\) and \(t_2\) respectively. If the ratio \(v_1: v_2\) is \(1: 3\), the ratio \(t_1: t_2\) will be
(A) \(10: 25\)
(B) \(25: 10\)
(C) \(1: 1\)
(D) \(1: 3\)
Problem 4
The SI unit of temperature is
(A) degree Fahrenheit \( ({ }^{\circ} \mathrm{F}) \)
(B) degree Celsius \( ({ }^{\circ} \mathrm{C}) \)
(C) degree Kelvin \( ({ }^{\circ} \mathrm{K}) \)
(D) None of the above
Problem 5
A convex lens \(L_1\) forms an image of the same size as that of the object at a distance of 24 cm . If the lens \(\mathrm{L}_1\) is replaced by another convex lens \(\mathrm{L}_2\), the image formed is magnified and erect. Therefore, the focal lenght of \(L_2\) is
(A) less than 12 cm
(B) 12 cm
(C) between 12 cm and 24 cm
(D) more than 24 cm
Problem 6
A wooden ball of density \(0.8 \mathrm{~g} / \mathrm{cm}^3\) is placed in water. The ratio of the volume above the water surface to that below the water surface is
(A) 0.25
(B) 0.20
(C) 2.0
(D) 4.0
Problem 7
A stone is released from an elevator moving upwards with an acceleration (a). The acceleration of the stone after the release is
(A) (a) upwards
(B) (\(\mathrm{g}-a)\) upwards
(C) (\(\mathrm{g}-a)\) downwards
(D) g downwards
Problem 8
A converging beam of light falls on a convex mirror of radius of curvature 20 cm , the point of convergence being 10 cm behind the mirror. The image is
(A) virtual and formed 10 cm in front of the mirror
(B) real and formed in front of the mirror
(C) formed at infinity
(D) virtual and formed 10 cm behind the mirror
Problem 9
When a sound wave moves through air along (X) axis, there is a variation in density of air in this direction. The graphical representation of this variation for two sound waves A and B is as shown. Which of the following statements is correct?
(A) Frequency of A is greater than that of B
(B) Velocity of B is greater than that of A
(C) Wavelength of B is greater than that of A
(D) Loudness of A is greater than that of B
Problem 10
In the figure shown below, each of the lenses has a focal length of 10 cm. Therefore, the image formed by the combination of lenses is
(A) virtual, erect and magnified
(B) virtual, inverted and diminished
(C) virtual, erect and diminished
(D) real, erect and diminished
Problem 11
A convex mirror used as the rear view mirror of a motor vehicle has a warning written on it - 'Objective in this mirror are nearer than they appear'. The reason for this warning is that
(A) the image is diminished
(B) the image distance is less than the focal length of the mirror
(C) the image distance is less than the object distance
(D) the image distance is more than the object distance
Problem 12
A uniform wire of resistance 36 ohm is bent into a circle. A battery is connected between points (A) and (B) as shown. The effective resistance between (A) and (B) is
(A) 36 ohm
(B) 30 ohm
(C) 6 ohm
(D) 5 ohm
Problem 13
On North Pole, when the surface of sea gets frozen due to cold weather, eskimos can still fish by cutting a portion of ice at the surface to find water underneath. This is possible because water
(A) has low thermal conductivity
(B) has high specific heat
(C) has high surface tension
(D) shows anomalous behaviour
Problem 14
A, DC current flows through a vertical wire in the downward direction. For an observer looking at the wire, the direction of magnetic field at a point between him and the wire is
(A) upward
(B) to the right
(C) to the left
(D) downward
Problem 15
A number of electric bulbs of rating 220 volt, 100 watt are to be connected in parallel to a 220 volt supply. If a 5 A fuse wire is used for this arrangement to bulbs, the maximum number of bulbs that can be included in the arrangement will be
(A) 10
(B) 11
(C) 22
(D) 44
Problem 16
In the circuit given below, AB is a thick copper wire and S is a switch. When the switch is closed, the effective resistance of the circuit will be
(A) 5 ohm
(B) \(6 / 5 \mathrm{ohm}\)
(C) 3 ohm
(D) zero
Problem 17
In figure (1) ammeter reads \(I_1\) and voltmeter reads \(V_1\). Similarly, in figure (2) ammeter reads \(I_2\) while voltmeter reads \(\mathrm{V}_2\). Then which of the following statements is correct?
(A) \(\mathrm{V}_1>\mathrm{V}_2\) and \(\mathrm{I}_1>\mathrm{I}_2\)
(B) \(\mathrm{V}_1>\mathrm{V}_2\) and \(\mathrm{I}_1<\mathrm{I}_2\)
(C)\(\mathrm{V}_1<\mathrm{V}_2\) and \(\mathrm{I}_1>\mathrm{I}_2\)
(D) \(\mathrm{V}_1<\mathrm{V}_2\) and \(\mathrm{I}_1<\mathrm{I}_2\)
Problem 18
The latent heat of fusion of a solid is the quantity of heat in joules required to convert
(A) 1 mg of the solid to liquid, without any change in temperature.
(B) 1 g of the solid to liquid, without any change in temperature.
(C) 100 g of the solid to liquid, without any change in temperature.
(D) 1000 g of the solid to liquid, without any change in temperature.
Problem 19
If the pressure of a given mass of a gas is reduced to half and temperature is doubled simultaneously, the volume will be-
(A) the same as above
(B) twice as before
(B) four times as before
(D) one forth as before
Problem 20
While picking up a pair of eye glasses dropped by a friend, you notice that they form an inverted image of the background and that the image is stretched horizontally as well. Your friend suffers from
(A) only myopia
(B) only hypermetropia
(C) only astigmatism
(D) hypermetropia as well as astigmatism
