Physics: CUET Mock Test - 9 - CUET MCQ

Physics: CUET Mock Test - 9 - CUET MCQ

Test Description

30 Questions MCQ Test CUET Mock Test Series - Physics: CUET Mock Test - 9

Physics: CUET Mock Test - 9 for CUET 2024 is part of CUET Mock Test Series preparation. The Physics: CUET Mock Test - 9 questions and answers have been prepared according to the CUET exam syllabus.The Physics: CUET Mock Test - 9 MCQs are made for CUET 2024 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests for Physics: CUET Mock Test - 9 below.
Solutions of Physics: CUET Mock Test - 9 questions in English are available as part of our CUET Mock Test Series for CUET & Physics: CUET Mock Test - 9 solutions in Hindi for CUET Mock Test Series course. Download more important topics, notes, lectures and mock test series for CUET Exam by signing up for free. Attempt Physics: CUET Mock Test - 9 | 40 questions in 45 minutes | Mock test for CUET preparation | Free important questions MCQ to study CUET Mock Test Series for CUET Exam | Download free PDF with solutions
Physics: CUET Mock Test - 9 - Question 1

Which of the following is a widely used variety of commercial resistor?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 1

A wire bound resistor is an electrical passive component that limits current. Wire-bound resistors are made by winding the wires of an alloy like manganin on an insulating base. They are relatively insensitive to temperature.

Physics: CUET Mock Test - 9 - Question 2

What is the use of a Van de Graff generator?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 2

Van de Graff generator is used to create a large amount of static electricity. A Van de Graff generator uses static electricity and a moving belt to charge a large metal sphere to a very high voltage. As the belt moves, electrons move from the rubber belt to the silicon roller, causing the belt to become positively charged and the roller to become negatively charged. As a result, it builds up positive charge.

 1 Crore+ students have signed up on EduRev. Have you?
Physics: CUET Mock Test - 9 - Question 3

What is the order of potential difference built up by the Van de Graff generator?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 3

A Van de Graff generator, by means of a moving belt and suitable brushes, transfers charge continuously to a large spherical conducting shell. As a result, a potential difference of the order of several million volts is built up and this can be used for accelerating charged particles.

Physics: CUET Mock Test - 9 - Question 4

When was Van de Graff generator invented and by whom?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 4

Van de Graff generator was invented by Robert Jemison Van de Graff on November 28, 1933. Robert Jemison invented the Van de Graff generator, which is a kind of high-voltage electrostatic generator that accelerates particles, while he was doing his PhD in Princeton University.

Physics: CUET Mock Test - 9 - Question 5

Find the true statement.

Detailed Solution for Physics: CUET Mock Test - 9 - Question 5

A Van de Graff generators produces large voltage and less current. A Van de Graff generator is an electrostatic generator which creates very high electric potentials. It produces very high voltage direct current electricity at low current levels.

Physics: CUET Mock Test - 9 - Question 6

Identify the type of modulation where the frequency of the modulated wave is equal to that of the carrier wave.

Detailed Solution for Physics: CUET Mock Test - 9 - Question 6

In Amplitude modulation, the modulating wave is superimposed on a high-frequency carrier wave such that the amplitude of the modulated wave varies as the amplitude of the modulating wave.

Physics: CUET Mock Test - 9 - Question 7

Why is AM used for broadcasting in the communication systems?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 7

Amplitude modulation (AM) is used for broadcasting because it avoids receiver complexity. Moreover, only a diode and a capacitor are sufficient to separate the audio signal from the amplitude-modulated wave.

Physics: CUET Mock Test - 9 - Question 8

A carrier of peak voltage 15 V is used to transmit a message signal. If the modulation index is 70%, then what will be the peak voltage of the modulating signal?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 8

Physics: CUET Mock Test - 9 - Question 9

‘X’ for an AM is the ratio of change in amplitude of the carrier wave to the amplitude of the original carrier wave. Identify ‘X’.

Detailed Solution for Physics: CUET Mock Test - 9 - Question 9

The modulation index for an AM wave is defined as the ratio of change in the amplitude of the carrier wave to the amplitude of the original carrier wave.

Physics: CUET Mock Test - 9 - Question 10

Suggest a possible communication channel for the transmission of a message signal that has a bandwidth of 200kHz.

Detailed Solution for Physics: CUET Mock Test - 9 - Question 10

The communication channel for the transmission of a message signal that has a bandwidth of 200kHz is FM radio. AM radio is the channel required for a message signal having a bandwidth of 5 MHz. Other options are not valid.

Physics: CUET Mock Test - 9 - Question 11

Identify the type of modulation where the modulating wave is superimposed on a high-frequency carrier wave.

Detailed Solution for Physics: CUET Mock Test - 9 - Question 11

In Amplitude modulation, the modulating wave is superimposed on a high-frequency carrier wave such that the amplitude of the modulated wave varies as the amplitude of the modulating wave. The frequency of the modulated wave is equal to the frequency of the carrier wave.

Physics: CUET Mock Test - 9 - Question 12

How can the noise be reduced in AM signal?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 12

Noise is a form of amplitude variations in the transmitted signal due to several factors such as the atmosphere, industries, etc. This noise can be reduced by increasing the deviation of the frequency of the signal.

Physics: CUET Mock Test - 9 - Question 13

Of the following which is the preferred modulation scheme for digital communication?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 13

Pulse code modulation is the one preferred for digital communication. Pulse codes are used to convert an analog signal to a digital one. It is the standard form of digital audio in computers, compact discs, etc.

Physics: CUET Mock Test - 9 - Question 14

What does AGC stand for?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 14

AGC stands for automatic gain control. Automatic gain control changes (AGC) the overall gain of a receiver automatically so that the strength of the received signal remains almost constant.

Physics: CUET Mock Test - 9 - Question 15

What is a rectifier used for?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 15

A rectifier is based on the fact that a forward bias p-n junction conducts and a reverse bias p-n junction does not conduct electricity. The rectifier is used to convert alternating current voltage (ac) to direct current voltage (dc).

Physics: CUET Mock Test - 9 - Question 16

What is the ripple factor for a half-wave rectifier?

Detailed Solution for Physics: CUET Mock Test - 9 - Question 16

For a half-wave rectifier,

r =1.21

Physics: CUET Mock Test - 9 - Question 17

Flow of charges in direction of electrons is called

Detailed Solution for Physics: CUET Mock Test - 9 - Question 17

The flow of electrons is termed electronic current. Electrons flow from the negative terminal to the positive.

Physics: CUET Mock Test - 9 - Question 18

If the length of the filament of a heater is reduced by 10% the power of the heater will

Detailed Solution for Physics: CUET Mock Test - 9 - Question 18

Power P= V2/R​
If length reduced 10% then new resistance of filament will be R′.
R′=R−10% of R
R′=0.9R
Now new power of heater is P2​
P2​= V2​​/R′ = V2/0.9R​​=1.1P
% increase power=11%

Physics: CUET Mock Test - 9 - Question 19

Potentiometer is

Detailed Solution for Physics: CUET Mock Test - 9 - Question 19

Potentiometer is a long wire of uniform cross section made of manganin.

Physics: CUET Mock Test - 9 - Question 20

The instrument for the accurate measurement of the e.m.f of a cell is

Detailed Solution for Physics: CUET Mock Test - 9 - Question 20
• Both potentiometer and voltmeter are devices to measure potential difference.
• EMF is the terminal p.d between the electrodes of a cell in open circuit, i.e., when no current is drawn from it.
• Potentiometer measures the potential difference using null deflection method, where no current is drawn from the cell; whereas voltmeter needs a small current to show deflection.
• So, accurate measurement of p.d is done using a potentiometer.
Physics: CUET Mock Test - 9 - Question 21

Drift is the random motion of the charged particles within a conductor,

Detailed Solution for Physics: CUET Mock Test - 9 - Question 21

The electrons in a conductor have random velocities and when an electric field is applied, they suffer repeated collisions and in the process move with a small average velocity, opposite to the direction of the field. This is equivalent to positive charge flowing in the direction of the field.

Physics: CUET Mock Test - 9 - Question 22

Potentiometer measures the potential difference more accurately than a voltmeter, because

Detailed Solution for Physics: CUET Mock Test - 9 - Question 22

Potentiometer measures the potential difference using null deflection method, where no current is drawn from the cell; whereas voltmeter needs a small current to show deflection. So, accurate measurement of p.d is done using a potentiometer.

Physics: CUET Mock Test - 9 - Question 23

A piece of copper and another of germanium are cooled from room temperature to 80K. The resistance

Detailed Solution for Physics: CUET Mock Test - 9 - Question 23
• Copper is a conductor and we know that for conductors, resistance is directly proprtional to temperature. Therefore on decreasing temperature resistance also decreases.
• Whereas, germanium is a semiconductor and for semiconductors, resistance is inversely proportional to temperature.
• So on decreasing temperature resistance increases.
Physics: CUET Mock Test - 9 - Question 24

In a potentiometer experiment, for measuring internal resistance of a cell, the balance point has been obtained on the fourth wire. The balance point can be shifted to fifth wire by

Detailed Solution for Physics: CUET Mock Test - 9 - Question 24

If the current due to the auxillary battery is decreased, the potential gradient will be decreases, so the balancing length increases.Thus null point will move to fifth wire.

Physics: CUET Mock Test - 9 - Question 25

Ammeter is always used

Detailed Solution for Physics: CUET Mock Test - 9 - Question 25

Ammeter is a device used to measure current. Since it has to allow the complete current flowing in the circuit through it, it has to be connected in series. For this reason, ammeters have very low values of resistances so that they do not add to the value of resistance connected in the circuit.

Physics: CUET Mock Test - 9 - Question 26

Kirchhoff’s second law is a consequence of

Detailed Solution for Physics: CUET Mock Test - 9 - Question 26

Kirchhoff's second law, also known as the Kirchhoff's voltage law (KVL) states that the sum of all voltages around a closed loop in any circuit must be equal to zero. This again is a consequence of conservation of energy.

Physics: CUET Mock Test - 9 - Question 27

A Wheatstone bridge is balanced for four resistors R1, R2, R3 and R4 with a Lech lanche cell between A and C and a galvanometer between B and D. The positions of the cell and the galvanometer are interchanged. The balance will

Detailed Solution for Physics: CUET Mock Test - 9 - Question 27

The balance point will not change . For balancing of wheatstone bridge four arms of resistors are responsible. Interchange the position of galvanometer and cell does not affect balancing of wheatstone bridge.

Physics: CUET Mock Test - 9 - Question 28

Resistance of a conductor is

Detailed Solution for Physics: CUET Mock Test - 9 - Question 28

According to Ohm’s law, V = IR. Therefore R= V/I

Physics: CUET Mock Test - 9 - Question 29

The electric current in a discharge tube containing a gas is due to

Detailed Solution for Physics: CUET Mock Test - 9 - Question 29

Thus, intensive recombinations of electrons and positive ions into neutral atoms and molecules occur. This results in the emission of light by the discharge, i.e., the negative glow is mainly due to a glow of recombination. Hence in electric discharge the electric current is due to both electrons and positive ions.

Physics: CUET Mock Test - 9 - Question 30

A steady current is passing through a linear conductor of non-uniform cross-section. The current density in the conductor is

Detailed Solution for Physics: CUET Mock Test - 9 - Question 30

Current density is equal to Electric current divided by a given surface area, or it is the current flowing per a given cross section area.
The current density decreases with increase in cross section area which means they are inversely proportional.

CUET Mock Test Series

8 docs|148 tests
Information about Physics: CUET Mock Test - 9 Page
In this test you can find the Exam questions for Physics: CUET Mock Test - 9 solved & explained in the simplest way possible. Besides giving Questions and answers for Physics: CUET Mock Test - 9, EduRev gives you an ample number of Online tests for practice

8 docs|148 tests