(Paper) Model Questions for Engineering Entrance Tests Part - 3

Model Questions for Engineering Entrance Tests Part - 3
( Physics) 

101. The material used for making a permanent magnet is
a. Copper
b. Brass
c. Iron
d. Steel
Ans: D

102. A monoatomic ideal gas initially at 170C is suddenly compressed to one eighth of its original volume. The temperature after compression is
a. 170C
b. 8870C
c. 1360C
d. none of the above
Ans: B

103. The separation between an object and screen is 120cm. You are given a convex lens of focal length 25cm taking the position object as origin location of lens to form a distinct image on the screen is
a. 30 & 90 cm
b. 40 & 80 cm
c. 35.5 & 84.5 cm
d. 45 & 75 cm
Ans: C

104. When the fast moving cathode ray particles are suddenly stopped by a solid target of high melting point
a. X- rays are produced
b. β- are produced
c. α- are produced
d. Positive rays are produced
Ans: D

105. The distance between a town and a factory is 30km. A man started to walk from the factory to the town at 6.30 am. While a cyclist left the town for the factory at 6.40 am riding at a speed of 18 km/hr. The man met the cyclist after walking 6 km. The time at which they met is
a. 7.30 am
b. 8.00 am
c. 8.10 am
d. 8.30 am
Ans: B

106. Static electricity can be produced by
a. Chemical reaction
b. Friction
c. Induction
d. Both by (b) & (c)
Ans: D

107. A hollow cylinder and a solid cylinder having the same mass and same same diameter are released from rest simultaneously from the top of an inclined plane. Which will reach the bottom first
a. The solid cylinder
b. The hollow cylinder
c. Both will reach the bottom together
d. The one having greater density
Ans: A

108. The equation for a stationary wave is given by y = cosx sint. The wave length is (where x and y are in cm)
a. 2π cm
b. π/2 cm
c. 4π cm
d. π cm
Ans: A

109. The ratio of the magnetic induction to the magnetizing field is called
a. Magnetic potential
b. Hysteresis
c. Susceptibility
d. Permeability
Ans: D

110. The moment of inertia of a body about an axis is I, and its angular acceleration is α. Then I α is equal to
a. Kinetic energy
b. The angular momentum
c. The torque
d. Momentum
Ans: C

111. The objective of a microscope forms
a. virtual and enlarged image
b. virtual and diminished image
c. real and enlarged image
d. real and diminished image
Ans: C

112. The ratio of the rise in temperature of a gas when compared adiabatically to that when compressed isothermally to the same extent is
a. Depends on the gas
b. More than 1
c. Less than 1
d. Equal to 1
Ans: B

113. A cell of emf 12 volt connected across a resistor R=7Ω draws a current of 1.5A. The internal resistance of the cell is
a. 0.5Ω
b. 1Ω
c. 1.5Ω
d. zero
Ans: B

114. Sound waves in air are:
a. longitudinal
b. transverse
c. longitudinal as well as transverse
Ans: A

115. The moment of momentum is called
a. Couple
b. Impulse
c. Angular momentum
d. Torque
Ans: C

116. A biconvex lens of glass (refractive index = 1.5) has faces of radii 20 cm each. Its focal length in air is
a. 30 cm
b. 20 cm
c. 21 cm
d. 3 cm
Ans: B

117. A cable is shortened to half its length. The maximum load it can support without exceeding its elastic limit
a. Is trebled
b. Is doubled
c. Is halved
d. Does not change
Ans: D

118. Wavelength of electromagnetic wave of frequency 100 KHz
a. 5×106 m
b. 3×103 m
c. 3×108 m
d. 4×106 m
Ans: B

119. Current flowing in a copper voltmeter is 0.4 A. The number of Cu++ ions deposited at the cathode per minute is
a. 1.5×1020
b. 3×1020
c. 4.5×1019
d. 0.75×1020
Ans: D

120. When water is filled in an empty vessel, its frequency
a. remains the same
b. decreases
c. increases
d. either increases or decreases
Ans: C

121. The slopes of isothermal and adiabatic curves are related as
a. Adiabatic curve slope = ½ × Isothermal curve slope
b. Isothermal curve slope = Adiabatic curve slope
c. Isothermal curve slope = γ × Adiabatic curve slope
d. Isothermal curve slope = γ × Isothermal curve slope
Ans: D

122. A body rotating with an angular velocity 20 rad/s comes to rest in 4 seconds. The angle turned in last second of its motion is
a. 2.50
b. 5 rad
c. 200
d. 2.5 rad
Ans: D

123. The pressure exerted by an ideal gas is proportional to
a. square of the velocity of the molecules
b. the mean velocity of the molecules
c. the mean square velocity of the molecules
d. the root mean square velocity of the molecules
Ans: C

124. The refractive index is the least for
a. Green light
b. Blue light
c. Red light
d. Yellow light
Ans: C

125. Compressed air in the tube of a wheel of a cycle at a normal temperature suddenly starts coming out from a puncture. The air inside:
a. starts becoming cooler
b. may become hotter or cooler depending upon the amount of water vapour present
c. starts becoming hotter
d. remains at the same temperature.
Ans: A

126. When a mass is rotating in a plane about a fixed point its angular momentum is directed along
a. The radius
b. The tangent to orbit
c. Line at an angle of 450 to the plane of rotation
d. The axis of rotation
Ans: D

127. Two unequal resistors are connected in parallel in a circuit. Then
a. The current is the same through both of them
b. Voltage drop is the same across them
c. There will be larger potential drop across them
d. Larger current flows through the larger resistance
Ans: B

128. When a body is positively charged it means that
a. Some protons have been added to it
b. Some electrons have been removed from it
c. Some protons have been removed from it
d. Some electrons have been added to it
Ans: B

129. If the sound in hydrogen is v, then in a mixture of hydrogen and oxygen in the ratio 5:1 by volumes, the speed of sound at same temperature and pressure is
a. (6.5)½ v
b. (5/6)½ v
c. (7/3)½ v
d. (7/3)½ v
Ans: D

130. A motor car tyre is pumped to 2 atmospheres at 150C when it bursts. Assume adiabatic expansion. The drop in temperature of air is: (for air γ = 1.4)
a. -560C
b. 410C
c. 560C
d. none of the above
Ans: C

131. A flask containing air at 270C at atmospheric pressure is corked up. A pressure of 2.5 atmosphere inside the flask would force the cork out. The temperature at which it will happen is
a. 67.50C
b. 750K
c. 5770C
d. 7500C
Ans: B

132. Two tuning forks of frequencies 252 Hz & 256 Hz sounded together produce beats. The frequency of resultant wave is
a. 252 Hz
b. 4 Hz
c. 254 Hz
d. 258 Hz
Ans: C

133. The number of images formed by the mirrors inclined at 450 of an object between them is
a. Infinite
b. Seven
c. One
d. Four
Ans: B

134. Out of the following the vector quantity is
a. electric charge
b. current
c. potential
d. electric field intensity
Ans: D

135. Dry air (γ = 1.5) at atmospheric pressure is suddenly compressed to one fourth of its original volume. The pressure will be
a. 3 atmosphere
b. 6 atmosphere
c. 8 atmosphere
d. 10 atmosphere
Ans: C

136. Two thermometers X and Y have ice points marked at 150 and 250 and steam points marked as 750 and 1250 respectively. When thermometer X measures the temperature of a bath as 600 on it, Y would measure the same temperature as
a. 600
b. 750
c. 1000
d. 1050
Ans: C

137. In the above question if the volume after compression is half the original volume, the final pressure after a long time is
a. greater than twice the initial pressure
b. equal to twice the initial pressure
c. equal to the initial pressure
d. equal to half of the initial pressure
Ans: B

138. Air in a cylinder is suddenly compressed by a piston, which is then maintained at the same position with the passage of time
a. the pressure decreases
b. the pressure increases
c. the pressure remains the same
d. the pressure may increase or decrease
Ans: A

139. An adiabatic process, at constant
a. Heat
b. Temperature
c. Pressure
d. Temperature and Pressure
Ans: A

140. A body of mass 2kg is moving along a horizontal surface. A force of 4N is needed to make it move with constant velocity 10 m/s along a straight line. If 4N force is suddenly reserved while the body is in motion
a. It will come to rest with a retardation of 4 m/s2
b. It will come to rest with a retardation of 4 m/s2 and then move with constant velocity in the opposite direction
c. It will not move at all
d. It will come to rest with a retardation of 2 m/s2
Ans: A

141. The electric potential at any point inside a charged hollow sphere
a. is the same
b. is zero
c. increases with distance from the centre
d. decreases as the distance from the centre increases
Ans: A

142. Number of electrons passing through a conductor per second to constitute a current of 1 micro ampere is
a. 6.25 × 1018
b. 6.25 × 1015
c. 6.25 × 1012
d. 1.6 × 10-19
Ans: C

143. Ω-m is the unit of
a. Resistance
b. Resistivity
c. Conductivity
d. Conductance
Ans: B

144. The quality of a tone:
a. decreases with loudness
b. varies directly as pitch
c. depend upon the overtones present
d. varies inversely as the amplitude
Ans: C

145. The isothermal bulk modulus of a perfect gas at atmospheric pressure is
a. 1.03×105 N/m2
b. 1.03×106 N/m2
c. 1.03×1010 N/m2
d. 1.03×1111 N/m2
Ans: A

146. The work done in adiabatic change in a gas depends on
a. Change in pressure
b. Change in volume
c. Change in temperature
d. None
Ans: B

147. A resistor R1, dissipates the power p when connected to a certain generator. If a resistance R2 is put in series with R1, the power dissipated by R1
a. increases
b. decreases
c. may increase or decrease
d. remains the same
Ans: B

148. If the diameter of closed tube is D, the value of end correction is
a. 0.15D
b. 0.6D
c. 1.2 D
d. 0.3D
Ans: D

149. Two thin lenses whose powers are +2D and -4D respectively. The power of the combination is
a. -2D
b. -4D
c. +4D
d. +2D
Ans: A

150. Gamma rays are
a. Streams of protons
b. Streams of electrons
c. Electromagnetic waves of long wavelengths
d. Electromagnetic waves of short wavelengths
Ans: D