1 . Which material is used in the manufacturing of electric heater coil?
[A] Copper
[B] Iron
[C] Nickel
[D] Nichrome
Correct Answer: D [Nichrome]
Notes:
Due to its resistance to oxidation and stability at high temperatures, Nichrome is widely used in electric heating elements, such as in appliances and tools. Typically, nichrome is wound in coils to a certain electrical resistance, and current is passed through it to produce heat.
2 . Which one of the following is an ohmic conductor?
[A] Germanium
[B] Silicon
[C] Carbon
[D] Silver
Correct Answer: D [Silver]
Notes:
Ohmic conductors are conductors that obey Ohm’s law, that is Voltage/Current ratio is constant. An Ohmic conductors resistance does not change with varying current. Metallic conductors are Ohmic conductors of which silver is the best with the least value of resistivity.
3 . Magnetic keepers are pieces of__:
[A] Nickel
[B] Cobalt
[C] Steel
[D] Soft iron
Correct Answer: D [Soft iron]
Notes:
Magnetic keepers are pieces of soft iron that are placed across the poles of a bar magnet or a horseshoe magnet. They help prevent the loss of magnetism. i.e. help retain the magnetic strength of the magnates placed together.
4 . Which of the following is arranged in order of decreasing conductivity?
[A] Copper, Aluminium, Steel, Silver
[B] Aluminium, Silver, Copper, Steel
[C] Copper, Silver, Aluminium, Steel
[D] Silver, Copper, Aluminium, Steel
Correct Answer: D [Silver, Copper, Aluminium, Steel]
Notes:
Copper ; 9% less conductive than silver; aluminium is 10% less conductive than copper; while steel is the least conductive among the given options. The most electrically conductive metal is silver.
5 . The spectrum of light was first explained by __:
[A] Neils Bohr
[B] Isaac Newton
[C] Albert Einstein
[D] Galileo Galilei
Correct Answer: B [Isaac Newton]
Notes:
In the 17th century, Isaac Newton discovered that prisms could disassemble and reassemble white light, and described the phenomenon in his book Opticks. He was the first to use the word spectrum (Latin for “appearance” or “apparition”) in this sense in print in 1671 in describing his experiments in optics.
6 . Why does a black board appears black in colour ?
[A] It reflects black colour
[B] It absorbs black colour
[C] It reflects all colours
[D] It absorbs all the colours
Correct Answer: D [It absorbs all the colours]
Notes:
When white light falls on an opaque body, it absorbs all the colours except onecolour which it reflects; this reflected colour is the colour of the body. The blackboard appears black because it absorbs all the colours. The white paper appears white because it reflects all the colours and absorbs no colour.
7 . Distant objects can be seen with the help of?
[A] cronometer
[B] telescope
[C] microscope
[D] spectroscope
Correct Answer: B [telescope]
Notes:
A telescope is an optical instrument designed to make distant objects appear nearer. It contains an arrangement of lenses, or of curved mirrors and lenses, by which rays of light are collected and focused and the resulting image magnified. Most telescopes fall into one of two main categories: refractor or reflector.
8 . Which of the following waves cannot be polarised?
[A] Radio
[B] Ultra violet
[C] Infrared
[D] Ultrasonic
Correct Answer: D [Ultrasonic]
Notes:
Only transverse waves (such as radio, ultraviolet and infrared waves) can be polarized since their vibrations can potentially occur in all directions perpendicular to the direction of travel. It is therefore possible to confine the vibrations to a single plane. However, sound waves are longitudinal in which vibrations are parallel to the direction of travel of the wave. The vibrations of a longitudinal wave occur along a single line, it is therefore not possible to confine that to a plane. So it cannot be polarized.
9 . Fibre optics work on which principle?
[A] scattering of light
[B] total internal absorption
[C] total internal reflection
[D] optical rotation
Correct Answer: C [total internal reflection]
Notes:
An optical fiber is a flexible, transparent fiber made of glass (silica) or plastic, slightly thicker than a human hair. It functions as a waveguide, or glight pipeh, to transmit light between the two ends of the fiber. Optical fibres working on principle based on total internal reflection (TIR) are widely used in endoscopy and fiber-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communication. Optical fibers typically include a transparent eladding material with a lower index of refraction. Light is kept in the core by total internal reflection. This causes the fiber to out as a wave guide.
10 . Which force helps swimmers float in water?
[A] Muscular force
[B] Frictional force
[C] Buoyant force
[D] Magnetic force
Correct Answer: C [Buoyant force]
Notes:
In order for an object to float, its buoyant force needs to be greater or equal to the weight of the water. To become more buoyant, swimmers use their upper body since it is the body’s centre of buoyancy due to the greater surface area.
11 . The first law of thermodynamics is simply the case of__:
[A] Charle’s law
[B] Newton’s law of cooling
[C] The law of heat exchange
[D] The law of conservation of energy
Correct Answer: D [The law of conservation of energy]
Notes:
The first law of thermodynamics is a version of the law of conservation of energy for thermodynamic systems. It states that the change in the internal energy of a system is equal to the heat added to the system plus the work done on the system.
12 . Steel is more elastic than rubber because it :
[A] requires larger deforming force
[B] is never deformed
[C] is deformed very easily
[D] is harder than rubber
Correct Answer: C [is deformed very easily]
Notes:
Elasticity is the capability of an object to return to its former shape once a load inducing strain is removed. Young Modulus or elastic modulus [tendency to be deformed elastically (i. e. , non-permanently) when a force is applied to it. Steel is more elastic than that of rubber because it requires far more deforming force than rubber.
13 . The temperature of boiling water in a steam engine may be high because :
[A] there are dissolved substances in water
[B] there is low pressure inside the boiler
[C] there is high pressure inside the boiler
[D] the fire is at very high temperature
Correct Answer: C [there is high pressure inside the boiler]
Notes:
In the boiler of a steam engine, there is a firebox where coal is shoveled into. The coal is kept burning at a very high temperature, and is used to heat the boiler to boil water producing a high pressure steam. The high-pressure steam expands and exits the boiler via steam pipes into the steam reservoir, the steam is then controlled by a slide valve to move into a cylinder to push the piston. The pressure of the steam energy pushing the piston turns the drive wheel in a circle, creating motion for the locomotive.
14 . The pitch of sound depends on its__:
[A] Frequency
[B] Intensity
[C] Velocity
[D] Amplitude
Correct Answer: A [Frequency]
Notes:
Pitch is a perceptual property that allows the ordering of sounds on a frequency-related scale. Pitch may be quantified as a frequency, but pitch is not a purely objective physical property; it is a subjective psycho-acoustical attribute of sound. When the frequency is high, the wavelength of the sound is shorter.
15 . Law of Inertia is also known as _________.
[A] Newton’s fist law of motion
[B] Newton’s second law of motion
[C] Newton’s third law of motion
[D] None of these
Correct Answer: A [Newton’s fist law of motion]
Notes:
According to Newton’s First Law of Motion, an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This is also known as Law of Inertia.
16 . If the temperature of a liquid is 32° F, what is its temperature in Celsius scale?
[A] 32° C
[B] 0° C
[C] 100° C
[D] 212° C
Correct Answer: B [0° C]
Notes:
The formulas for converting between degree Celsius and degree Fahrenheit are
17 . 0°K is equivalent to which of the following in Centigrade?
[A] 273°C
[B] -273°C
[C] 0°C
[D] 100°C
Correct Answer: B [-273°C]
18 .Which of the following is the SI unit of luminous emittance?
[A] Lux
[B] Candela
[C] Lumen
[D] Lumen second
19 . A system exhibiting Simple Harmonic Motion (SHM) must possess__:
[A] Elasticity as well as inertia
[B] Elasticity, inertia and an external force
[C] Elasticity only
[D] Inertia only
Correct Answer: A [Elasticity as well as inertia]
20 . Which of these is an acceptor impurity?
[A] Phosphorus
[B] Arsenic
[C] Antimony
[D] Indium
Correct Answer: D [Indium]
21 . Which of the following is not a characteristic of a solid ?
[A] High compressibility
[B] High density
[C] Regular shape
[D] High rigidity
Correct Answer: A [High compressibility]
22 .0°K is equivalent to which of the following in Centigrade?
[A] 273°C
[B] -273°C
[C] 0°C
[D] 100°C
Correct Answer: B [-273°C]
23. Wheelbarrow is a type of which class of lever?
[A] Class 1 Level
[B] Double Class 1 Lever
[C] Class 2 Lever
[D] Class 3 Lever
Correct Answer: C [Class 2 Lever ]
24 . What do we call the ratio of change in collector-emitter voltage to the resulting change in the collector current at constant base current, when the transistor is being used in Common Emitter configuration?
[A] Input dynamic resistance
[B] Output dynamic resistance
[C] Output emitter Current
[D] Input emitter Current
Correct Answer: B [Output dynamic resistance]
25 .
Which of the following is the name given to electrons moving at high speed?
[A] Alpha particles
[B] Beta particles
[C] Gamma particles
[D] None
Correct Answer: B [Beta particles]
26 . Which of the following element has an isotope named as Tritium?
[A] Helium
[B] Carbon
[C] Titanium
[D] Hydrogen
Correct Answer: D [Hydrogen]
27 . Which of the following is correct about Permeability of free space?
[A] It is a scalar quantity
[B] Its S.I unit is T m A-1
[C] Both a and b
[D] None of the above
Correct Answer: C [Both a and b]
28 . Which of the following is correct NOT correct about inert electrodes?
[A] They serve as source of electrons
[B] They take part in the chemical reaction
[C] Both a and b
[D] None of the above
Correct Answer: B [They take part in the chemical reaction]
29 . What is the equivalent internal resistance of a series combination of n cells?
[A] the arithmetic mean of their internal resistance
[B] the product of their individual internal resistance
[C] the sum of their individual internal resistance
[D] the sum of the reciprocal of their individual internal resistance
Correct Answer: C [the sum of their individual internal resistance]
30 . Which of the following is a law of reflection?
[A] angle of incidence is equal to the angle of reflection
[B] angle of incidence is equal to twice the angle of reflection
[C] angle of incidence is equal to half of the angle of reflection
[D] angle of incidence is always complimentary to the angle of reflection
Correct Answer: A [angle of incidence is equal to the angle of reflection]
31 . Which of the following is true about the focal length of a spherical mirror?
[A] it is equal to its radius of curvature
[B] it is equal to half its radius of curvature
[C] it is equal to twice its radius of curvature
[D] None of the above
Correct Answer: B [it is equal to half its radius of curvature]
32 . What are the dimensions of Co-efficient of volume expansion?
[A] T-1 K-1
[B] M2 K-1
[C] K-1
[D] M1 K-2
33 . Which of the following are Green house gases?
[A] Carbon dioxide
[B] Methane
[C] Nitrous oxide
[D] All of the above
Correct Answer: D [All of the above]
34 . Which of the following represents the speed of a sound wave?
[A] wavelength x frequency
[B] 2 x wavelength x frequency
[C] wavelength/frequency
[D] (wavelength x frequency)/2
Correct Answer: A [wavelength x frequency]
35 . What happens to the frequency of the pendulum if it is suspended from the ceiling of the lift moving up ward with constant acceleration?
[A] it decreases
[B] it increases
[C] may increase or decrease
[D] No change
Correct Answer: B [it increases]
36 . Which of the following represents angular frequency of a body?
[A] twice the frequency of the body
[B] product of frequency of the body with π
[C] half the frequency of the body
[D] product of frequency of the body with 3 π
Correct Answer: A [twice the frequency of the body]
37 . On which of the following factors the breaking stress depends?
[A] Area of cross-section
[B] length of the material
[C] Nature of the material
[D] None of the above
Correct Answer: C [Nature of the material]
38 . Which of the following is the unit of Strain?
[A] Newton
[B] Kg
[C] Watt
[D] None of the above
Correct Answer: D [None of the above]
39 . What happens to the orbital velocity of a satellite when the radius of orbit is increased?
[A] it decreases
[B] it increases
[C] it remains same
[D] None of the above
Correct Answer: A [it decreases]
40 . In comparison to the gravitational force the earth exerts on the moon, the gravitational force the moon exerts on earth ________?
[A] will be greater
[B] will be lesser
[C] will be same
[D] None of the above
Correct Answer: C [will be same]
41 . What is Young’s Modulus?
[A] ratio of longitudinal strain to normal stress
[B] product of normal stress of longitudinal strain
[C] ratio of normal stress to longitudinal strain
[D] ratio of normal stress to lateral strain
Correct Answer: C [ratio of normal stress to longitudinal strain
42 . What will be the total energy of a satellite moving around the earth in a circular orbit with speed v and having mass m.
[A] -1/2 m v 3
[B] 2 m v 2
[C] 1/2 m v 3
[D] -1/2 m v 2
Correct Answer: D [-1/2 m v 2]
43 . An orbital velocity of a satellite does not depend on which of the following?
[A] Radius of the planet
[B] Mass of the planet
[C] Radius of orbit
[D] Mass of the satellite
Correct Answer: D [Mass of the satellite]
44 . The ratio of the magnitude of the external force applied on a body to the magnitude of acceleration produced in its motion is known as:
[A] Inertial Mass
[B] Angular Momentum
[C] Gravitational Potential
[D] Gravitational Constant
Correct Answer: A [Inertial Mass]
45 . Which of the following is true about the effect of altitude on the value of acceleration due to gravity?
[A] The acceleration due to gravity decreases with height
[B] The acceleration due to gravity increases with height
[C] The acceleration due to gravity is not dependent on height
[D] None of the above
Correct Answer: A [The acceleration due to gravity decreases with height]
46 . What kind of energy is stored in the spring of a watch?
[A] Kinetic
[B] Potential
[C] Heat
[D] Chemical
Correct Answer: B [Potential]
47 . What is the absolute unit of power in c.g.s system?
[A] dyne
[B] erg
[C] watt
[D] erg s-1
Correct Answer: D [erg s-1]
48 . Which of the following is correct about the coefficient of limiting friction between any two surfaces in contact?
[A] it is equal to twice the tangent of angle of friction
[B] it is equal to twice the sine of angle of friction
[C] it is equal to the tangent of angle of friction
[D] it is equal to the sine of angle of friction
Correct Answer: C [it is equal to the tangent of angle of friction]
49 . Which of the following statements regarding vectors is NOT correct?
[A] A unit vector is dimensionless
[B] A vector cannot be divided by a vector
[C] A vector changes, when it is displaced to itself
[D] Current is not a vector quantity
Correct Answer: C [A vector changes, when it is displaced to itself]
50 . What is the range of Strong Nuclear force?
[A] Infinite
[B] Very short Subnuclear size
[C] Very short Nuclear size
[D] None
Correct Answer: C [Very short Nuclear size]
