1. A Jet engine works on the principle of conservation of :

A. linear momentum B. angular momentum C. energy D. mass

Answer - Option A
Explanation -
A jet engine works on the principle of conservation of linear momentum.
2. The surface temperature of the Sun is nearly :

A. 2000º K B. 4000º K C. 6000º K D. 8000º K

Answer - Option C
Explanation -
Surface temperature of the sun in nearly 6000º K.
3. If the electrical resistance of a typical substance suddenly drops to zero, then the substance is called :

A. super conductor B. semiconductor C. conductor D. insulator

Answer - Option A
Explanation -
When the electrical resistance of a typical substance suddenly drops to zero this phenomenon is called as super conductors.
4. A spherical air bubble is embedded in a piece of glass. For a ray of light passing through the bubble, it behaves like a :

A. converging lens. B. diverging lens. C. piano-converging lens D. piano-diverging lens.

Answer - Option B
Explanation -
A spherical air bubble behaves like a diverging lens.
5. ‘The stars seem to be higher on the sky than they actually are'. This can be explained by:

A. atmospheric refraction. B. dispersion of light. C. total internal reflection. D. diffraction of light.

Answer - Option A
6. Which one among the following is not a source of renewable energy ?

A. Hydroelectricity B. Solar energy C. Fuel cell D. Wind energy

Answer - Option C
Explanation -
Fuel cell is not a source of renewable energy
7. Mass of B is four times that of A, B moves with a velocity half that of A. Then B has:

A. kinetic energy equal to that of A. B. half the kinetic energy of A C. twice the kinetic energy of A D. kinetic energy one-fourth of A.

Answer - Option A [latex]\frac{}{}[/latex]
Explanation -
Suppose mass of A = m
i.e, mass of B = 4m
Velocity of A = v
i.e, Velocity of B = [latex]\frac{v}{2}[/latex]
Kinetic energy of A = [latex]\frac{1}{2} m {v}^{2}[/latex]
Kintenic energy of B = [latex]\frac{1}{2} 4m {(\frac{v}{2})}^{2}[/latex]
= [latex]\frac{1}{2} 4m \frac{{v}^{2}}{4} [/latex]
= [latex]\frac{1}{2} m {v}^{2}[/latex]
So kinetic energy B = Kinetic energy A
8. In a pressure cooker cooking is "faster because the increase in vapour pressure :

A. increases the specific heat. B. decreases the specific heat. C. decreases the boiling point. D. increases the boiling point.

Answer - Option D
Explanation -
We know that
Pressure ∝ Temperature
As the increase in vapour pressure, increases the boiling point.
9. Magnets attract magnetic substances such as iron, nickel, cobalt etc. They can also repel :

A. paramagnetic substances. B. ferromagnetic substances. C. diamagnetic substances. D. non-magnetic substances

Answer - Option C
Explanation - Magnets attract magnetic substance such as iron, nickle, cobalt etc they also repel diamagnetic substances.
10. When a ray of light is going from one medium to another, its :

A. wavelength remains same. B. frequency remains same. C. frequency increases. D. wavelength increases.

Answer - Option B
Explanation -
When a ray of light is going from one medium to another its frequency remains same and wavelength decreases.
11. A body initially at rest is acted upon by a constant force. The rate of change of its kinetic energy varies :

A. linearly with square root of time. B. linearly with time. C. linearly with square of time. D. inversely with time

Answer - Option C
Explanation -
A body initially at rest is acted upon by a constant force. The rate of change of its kinetic energy varies linearly with square of time.
12. Which one among the following statements is correct ?

A. Convex mirrors are used by doctors to examine oral cavity B. Concave mirrors are used as reflectors C. Convex mirrors are used as reflectors D. Convex mirrors should be used for shaving

Answer - Option D
Explanation -
Convere lense of large focal length is used for sharing. It is also used in solar cooker.
13. Bats can ascertain distances, directions, nature and size of the obstacles at night. This is possible by reflection of the emitted :

A. ultrasonic waves from the bat. B. ultrasonic waves from the distant objects. C. supersonic waves from the bat. D. supersonic waves from the distant objects.

Answer - Option C
Explanation -
Emission of reflected supersonic waves from the bat can ascertain distance, directions, nature and size of obstacle at night.
14. Light travels slower in glass than in air because:

A. refractive index of air is less than that of glass. B. refractive index of air is greater than that of glass C. density of glass is greater than that of air. D. density of glass is less than that of air.

Answer - Option A
Explanation - Light travels sloven in glass than in air because refractive index of air is less than that of glass.
15. The lines of force of a uniform magnetic field :

A. must be convergent. B. must be divergent. C. must be parallel to each other. D. intersect.

Answer - Option C
Explanation -
The lines of force of a uniform magnetic field must be parallel to each other.

1. As the speed of charged particle increases in a cyclotron, (choose True (T) or False (F)) (a) the particle moves to a larger circle (b) there is relativistic change in the mass of the particle (c) frequency of the cyclotron has to be adjusted

A. F, F, F B. T, T, T C. T, F, T D. T, T, F

Answer - Option B
Explanation -
All 3 points are true about charged particle in cyclotron whose speed increases. Particle moves to a larger circle, its relativistic mass changes because of speed change and frequency of cyclotron has to be adjusted.
2. The formula R = [latex]\frac{{R}_{1} {R}_{2}}{{R}_{1} + {R}_{2}}[/latex] represents

A. series connection B. parallel connection C. bridge connection D. linear connection

Answer - Option B
Explanation -
When two resistances are in parallel, the formula gives the value of combined resistance of the circuit.
3. The earth conductor provides a path to ground for

A. circuit current B. leakage current C. over current D. high voltage

Answer - Option B
Explanation -
Earth conductor allows path for the leakage current in the body of the equipment or tool to ground.
4. If the mass of sun, earth and distance between them is respectively M, m and r; work done by the sun's gravity on earth for one revolution round the sun is

A. 0 B. [latex]\frac{GMm}{{r}^{2}}[/latex] C. [latex]\frac{GMm}{r}2\pi[/latex] D. [latex]\frac{GMm}{{r}^{2}}2 \pi[/latex]

Answer - Option A
Explanation -
Work done is zero because force is always perpendicular to the direction of movement of the earth. Also another way to look at this is earth returns to the same point after one revolution so work done must be zero as there are no latent energy forms involved.
5. The choke of a tube light works on the principle of

A. bi-metallic B. capacitance C. inductance D. ionization

Answer - Option C
Explanation -
Choke works on inductance principle. The function of choke is to provide high voltage enough for ionization to take place in a tube light and after establishment and sustenance of ionization, limit the voltage across the tube. That is the reason why a tube fuses when the choke is shorted.
6. In the figure below, what is the acceleration of body with mass [latex]{m}_{2}[/latex], given g is the acceleration due to gravity (assume pulley and surfaces are smooth)

A. g B. [latex]\frac{{m}_{1} + {m}_{2}}{{m}_{1}}[/latex]g C. [latex]\frac{{m}_{1} + {m}_{2}}{{m}_{2}}[/latex]g D. [latex]\frac{{m}_{2}}{{m}_{1} + {m}_{2}}[/latex]g

Answer - Option d
Explanation -
Force = m.a Here m = [latex]{m}_{1} + {m}_{2}[/latex] But force applied is [latex]{m}_{2}[/latex] g. Therefore acceleration = F/m
7. Which of the following statements is correct?

A. Speed of light in vacuum is 3 × [latex]{10}^{8}[/latex] m/s B. Speed of light is different for different colours C. Speed of light is different in different media D. All of the above

Answer - Option D
Explanation -
All the statements are correct. Speed of light changes in different media and it is different for different colours in media other than vacuum.
8. In Heisenberg's Uncertainty principle, the uncertainty of momentum and position of a particle can be

A. reduced using smaller wavelength of probing light B. reduced using larger wavelength of probing light C. reduced using high energy probe particles accelerated by cyclotron D. can't be reduced as it is fundamentally inherent

Answer - Option D
Explanation -
The uncertainty of position and momentum of particle in Heisenberg's Uncertainly principle cannot be reduced because it is inherent.
9. The speed of sound in air is approximately equal to :

A. 3 × [latex]{10}^{8}[/latex] m/s B. 330 m/s C. 5000 m/s D. 1500 m/s

Answer - Option B
10. 'When a body is wholly or partially, immersed in a fluid, it experiences an upthrust equal to the weight of the fluid displaced'. This is known as:

A. Pascal's principle B. Archimedes principle C. Stoke's law D. Newton's Laws of Motion

Answer - Option B
Explanation -
Archimedes' principle states that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the body displaces and acts in the upward direction at the center of mass of the displaced fluid.
11. Which one of the following is not a scalar quantity?

A. Volume B. Mass C. Force D. Length

Answer - Option C
Explanation -
Force is a vector quantity. F = m.a and the direction of acceleration will determine the direction of force.
12. The resultant of two forces P and Q acting at an angle 0, is given by :

A. [latex]\sqrt{{P}^{2} + {Q}^{2} + 2tan θ}[/latex] B. [latex]\sqrt{{P}^{2} + {Q}^{2} + 2sin θ}[/latex] C. [latex]\sqrt{{P}^{2} + {Q}^{2} + 2cos θ}[/latex] D. P + Q + 2PQtan θ

Answer - Option C
Explanation -
Whenever two vector quantities are added, their resultant vector is given by this formula.
[latex]\sqrt{{P}^{2} + {Q}^{2} + 2cos θ}[/latex]
13. A cyclotron is a :

A. Bunch of Gamma Rays B. High Frequency Oscillator C. Particle Accelerator D. None of these

Answer - Option C
Explanation -
A cyclotron accelerates charged particles outwards from the center along a spiral path. The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying (radio frequency) electric field.
14. The nucleus of an atom generally, contains :

A. Protons and Neutrons B. Protons and Electrons C. Electrons and Neutrons D. Only Neutrons

Answer - Option A
Explanation -
Both protons and neutrons are found in the nucleus and are together called nucleons. However, electrons revolve in orbits outside of the nucleus.
15. A bullet is fired vertically upwards with a velocity of 196 m/sec. What is the maximum height reached by the bullet ? (Assuming g = 9.8 m/[latex]{sec}^{2}[/latex] )

A. 1960 m B. 196 m C. 980 m D. 490 m

Answer - Option A
Explanation -
[latex]{v}^{2} - {u}^{2}[/latex]= 2as
0 - [latex]{(196)}^{2}[/latex] = -2 * 9.8 * s
s = 1960

1. In a classical blood pressure measuring instrument in which the doctor observes the rise and fall of mercury, the hand air pump is attached to a-

A. Isobar B. Transducer C. Manometer D. Mercury column

Answer - Option C
Explanation -
Manometer is an instrument in which doctor observes the rise and fall of mercury.
2. Conservation of energy corresponds to which law of thermodynamics?

A. Zeroth law B. First law C. Second law D. Third law

Answer - Option B
Explanation -
First law also known as law of conservation of energy, states that energy can neither the created not be destroyed in an Isolated system.Second law of thermodynamics states hot the entropy of an isolated system always increase.
Third law of thermodynamics states that entropy of a system approaches a confound value as the temperature approaches absolute zero.
i.e, Option (B) is correct.
3. In our house when we switch on heavy load appliances, we notice that there is slight dip in the glow of the bulb that was already switched on. This is due to-

A. Heavy current drawn by heavy load B. Additional resistance added to the circuit C. Resistance of electrical wiring D. Resistance of part of the circuit decreasing from infinity to a positive value

Answer - Option A
Explanation -
Heavy current drawn by heavy load because it has low resistance and takes more power.
4. What is the boiling point of water in Kelvin Scale?

A. 100 K B. 273 K C. 373 K D. 300 K

Answer - Option C
Explanation -
Boiling point of water is 373K.
5. Acid rain is caused by:

A. CO and [latex]{CO}_{2}[/latex] B. [latex]{SO}_{2} and {O}_{2}[/latex] C. [latex]{SO}_{2} and {NO}_{2}[/latex] D. [latex]{NO}_{2} and {O}_{2}[/latex]

Answer - Option C
Explanation -
Acid rain is caused by chemical reaction when compounds like sulphur dioxide and nitrogen oxides are released into air, these substance rise very high into atmosphere, where they mix and react with water, oxygen and other chemicals to form acid rain.
i.e, Option (C) is correct.
6. Which planet has hot turbulent atmosphere dominated by carbon-di-oxide?

A. Venus B. Mars C. Jupiter D. Neptune

Answer - Option A
Explanation -
Planet Venus has hot-turbulent atmosphere dominated by [latex]{CO}_{2}[/latex]
7. A tunic fork when sounded together with another tuning fork of known frequency of 240 Hz, emits 2 beats. On loading the tuning fork of known frequency the number of heats heard are one per second. The frequency of the tuning fork is:

A. 241Hz B. 242 Hz C. 239 Hz D. 238 Hz

Answer - Option D
Explanation -
The frequency of tuning fork is = 240 – 2 = 238 Hz
8. Tachometer (or) Tachometer is an instrument for measuring-

A. rpm B. Torque C. Rotational kinetic energy D. Distances

Answer - Option D
Explanation -
tachometer can measure rpm.
i.e, Option (A) is correct.
9. Which of the following is NOT used for measurement of temperature?

A. Thermocouples B. Thermostats C. Pyrometers D. All are used

Answer - Option D
Explanation -
l devices are used to measure temperature.
10. Aluminium is commonly used as conduct or material in transmission lines compared to copper because:

A. It is more conductive B. Its tensile strength is more C. It is costlier D. It is cheaper and lighter

Answer - Option B
Explanation -
Copper has highest conductivity but low tensile strength compare to aluminium as copper is must costly so it is no used for transmission line.
11. Find the distance of object from a concave mirror of focal length 10 cm so that the size of its real image is four times the size of the object.

A. 7.5 cm B. 5 cm C. 2.5 cm D. 12.5 cm

Answer - Option D
Explanation -
[latex]\frac{1}{u} + \frac{1}{4u} = \frac{1}{f}[/latex]
[latex]\frac{5u}{4{u}^{2}} = \frac{1}{10}[/latex]
i.e, u = 12.5 cm.
12. A barometer measures :

A. Absolute pressure B. Atmospheric pressure C. Gauge pressure D. Vacuum

Answer - Option B
Explanation -
A barometer is an instrument used to measure atmospheric pressure.
i.e, Option (B) is correct
13. Which one of the following has the dimensions of pressure ?

A. [latex]ML{T}^{-2}[/latex] B. [latex]M{L}^{-1}{T}^{-2}[/latex] C. [latex]M{L}^{-2}{T}^{-2}[/latex] D. [latex]M{L}^{-1}{T}^{-1}[/latex]

Answer - Option B
Explanation -
Pressure = [latex]\frac{Force}{Area} = \frac{mass * acceleration}{Area}[/latex]
[latex]\frac{{M}^{1}{L}^{1}{T}^{-2}}{{L}^{2}}[/latex]
[latex]M{L}^{-1}{T}^{-2}[/latex]
i.e, Option (b) is correct
14. The refractive index of water is [latex]\frac{4}{3}[/latex] What is the speed of light in water ?

A. 2.25 × [latex]{10}^{8}[/latex] m/s B. 4 × [latex]{10}^{8}[/latex] m/s C. 1.5 × [latex]{10}^{8}[/latex] m/s D. 2.67 × [latex]{10}^{8}[/latex] m/s

Answer - Option A
Explanation -
Refractive index = [latex]\frac{C}{V}[/latex]
i.e, [latex]\frac{4}{3}[/latex] = [latex]\frac{3 × {10}^{8}}{V}[/latex]
V = [latex]\frac{9 × {10}^{8}}{4}[/latex] = 2.25 × [latex]{10}^{8}[/latex] m/s