MCQExams
0:0:1
CBSE
JEE
NTSE
NEET
Practice
Homework
×
CBSE Questions for Class 10 Physics Magnetic Effects Of Electric Current Quiz 3 - MCQExams.com
CBSE
Class 10 Physics
Magnetic Effects Of Electric Current
Quiz 3
Write the SI unit of electric power.
Report Question
0%
Watt
0%
Kilo watt
0%
Joule
0%
Kilowatt hour
Explanation
SI unit of electric power is Watt
1 Watt = 1 Volt $$\times$$ 1 ampere.
Neutral wire is usually insulated with:
Report Question
0%
Red colour
0%
Green colour
0%
Black colour
0%
None of these
Explanation
In our houses, we receive AC electric power of $$220\ V$$ with a frequency of $$50\ Hz$$. One of the wires in this supply is with red insulation, called live wire. The other one is of black insulation, which is a neutral wire. The potential difference between the two is $$220\ V$$. The third is the earth wire that has green insulation and this is connected to a metallic body deep inside the earth. It is used as a safety measure to ensure that any leakage of current to a metallic body does not give any severe shock to a user.
In the field of electromagnetism, the term 'EMI' stands for:
Report Question
0%
Electromotive Impact
0%
Electromagnetic Induction
0%
Electromotive inertia
0%
none of these
Explanation
In the field of electromagnetism, the term EMI stands for Electro Magnetic Induction.
In the statement of Fleming's left hand rule, magnetic field is represented by
Report Question
0%
thumb
0%
fore finger
0%
middle finger
0%
none
Explanation
According to Fleming's left-hand rule, one needs to stretch the thumb, forefinger, and middle finger of the left hand such that they are mutually perpendicular. If the first finger points in the direction of the magnetic field and the second finger in the direction of the current, then the thumb will point in the direction of motion or the force acting on the conductor.
Name the colour used in insulated wires of electrical appliance.
Report Question
0%
Red
0%
Green
0%
Black
0%
All of these
Explanation
The three different colors of insulation used in the electrical wires are red, black, and green. In old convention, the red wire is the live wire, the black wire is neutral and the earth wire is given green insulation. In new convention, the brown wire is the live wire, the light blue wire is neutral and the earth wire is given green-yellow insulation.
Which colour is used for earth wire?
Report Question
0%
Green
0%
Yellow
0%
Both of these
0%
None of these
Explanation
The green one as well yellow color is used as Earth's wire. This is because the green and yellow type wires are for grounding purposes or we can say earthen purposes. Green colored wires are used in an electric circuit for grounding.
$$15 A$$ current rating used for ________ appliances.
Report Question
0%
Low power rating
0%
High power rating
0%
Medium power rating
0%
All
Each electrical appliance is provided with a _______ core flexible cable. Fill in the blank.
Report Question
0%
3
0%
2
0%
1
0%
4
Explanation
Each electrical appliance is provided with three (3) core flexible cables. The insulation on the three wires is of different colours i.e Brown for live wire, blue for neutral wire and green or yellow for earth wire.
On what principle electric motor works?
Report Question
0%
Principle of force experienced by current carrying conductor in magnetic field
0%
Principle of current experienced by current carrying conductor in magnetic field
0%
Principle of force experienced by current carrying conductor in electric field
0%
None of the above
Explanation
An electric motor converts electrical energy into mechanical energy.
Current is passed through an armature, which placed under an external magnetic field experiences force on its arms and causes the armature to rotate.Hence based on the principle of force experienced by current carrying conductor in magnetic field.
The direction of the force acting on a current carrying conductor when placed in a magnetic field can be obtained by
Report Question
0%
Fleming left hand rule
0%
Fleming right hand rule
0%
Both
0%
None
Explanation
Fleming left hand rule is used to find out the direction of motion of a current carrying conductor when placed in a magnetic field.
According to this rule, stretch the thumb, forefinger and middle finger of your left hand such that they are mutually perpendicular. If the first finger points in the direction of magnetic field and the second finger in the direction of current, then the thumb will point in the direction of motion or the force acting on the conductor
Which of the following best describe the electromagnetic induction?
Report Question
0%
The ability of a changing magnetic field to induce a voltage in a conductor
0%
The ability of a conductor to generate a magnetic field
0%
The ability of a static magnetic field to induce a voltage in a conductor
0%
The ability of a permanent magnet to induce a voltage in a coil
0%
The ability of a conductor to induce a magnetic field
Explanation
Electromagnetic induction
is a process where a conductor placed in a changing magnetic field (or a conductor moving through a stationary magnetic field) causes the production of a voltage
across the conductor.
Changing magnetic field causes a change in flux which gives rise to induced emf.
Also, a moving rod in a uniform magnetic field would mean moving electrons in a magnetic field which would exert force on them to move in a particular direction in the rod, thus creating a potential difference across ends.
A straight wire of
0.3 m
carrying a current of 2 A in the downward direction is placed in a magnetic field of 0.1 T as shown in the figure. Find out the direction of the force on the wire?
Report Question
0%
Into the page
0%
Out of the page
0%
Toward the top of the page
0%
Toward the bottom of the page
0%
To the left
Explanation
The direction of magnetic force on a current carrying conductor placed perpendicular to the magnetic field is given by Fleming's left hand rule. Using this rule, it can be concluded that the direction of force on wire is out of the page.
A current carrying conductor.
Report Question
0%
Experience a force when it is in magnetic field
0%
Does not experience a force when it is in magnetic field
0%
Experiences the force only when the field is electromagnetic in nature
0%
None of the above
Explanation
As per right hand thumb rule, when a current carrying conductor is in magnetic field, it experiences force as
$$F=IlB\sin\theta$$
According to new convention,_____colour is used for live wire. Fill in the blank.
Report Question
0%
Red
0%
Brown
0%
Light blue
0%
Green
Explanation
According to new convention, brown colour is coded for live wire, light blue is coded for neutral wire and green or yellow is coded for earth wire.
Change in number of magnetic field lines induces
Report Question
0%
current in coil
0%
EMF in the coil
0%
frequency in coil
0%
both A and C
Explanation
As per Faraday's law, the change in magnetic flux associated with coil produces an EMF in the coil. Whenever there is a change in magnetic flux associated with a coil, an EMF is induced in the coil. Magnetic flux is defined as the number of field lines passing normally through a given area. When magnetic flux changes, obviously, it means that, the number of magnetic field lines change.
When the plane of the rectangular coil is parallel to the direction of the magnetic field in a dynamo, then
Report Question
0%
Induced current will be zero.
0%
Induced current is maximum.
0%
AC is produced.
0%
DC is produced.
Explanation
When the rectangular coil is parallel to the direction of the magnetic field, the induced current is zero. It is because, effectively, zero or no magnetic field lines are linked to the cross-section of the coil. Induced voltage/ current can be zero only if:
the number of magnetic field lines linked with the coil doesn't change with time
or there are no magnetic field lines linked to the coil at all.
The change in magnetic field lines can be achieved by:
by relative motion between the magnet and the coil
varying the current in the primary coil which varies the number of magnetic field lines linked with the secondary coil.
If the above two conditions are not met, then also the induced current is zero.
The figure showing Fleming's left hand rule is given. Which figure or thumb shows the direction of flow of electric current?
Report Question
0%
First finger
0%
Second finger
0%
Thumb
0%
Small finger
Explanation
The direction of force or motion of a current-carrying wire placed in a magnetic field is given by Fleming's left-hand rule. The second finger gives the direction of the electric current.
Which of the following is not correct about the magnetic field lines?
Report Question
0%
The magnetic field lines of a magnet form continuous closed loops.
0%
The tangent to the field line at a given point represents the direction of the net magnetic field B at that point.
0%
The larger the number of field lines crossing per unit area, the stronger is the magnitude of the magnetic field B.
0%
The magnetic field lines may intersect to each other in certain conditions.
Explanation
The magnetic field lines do not intersect.
.................. gave the principle of Electromagnetic Induction.
Report Question
0%
Volta
0%
Ampere
0%
Faraday
0%
Orested
Which statement is wrong from the following?
Report Question
0%
The earthing wire is green coloured
0%
In India, current flowing through wire is AC and its frequency is $$50Hz$$
0%
In India, voltage between two wires is $$110V$$
0%
T.V., tube light, bulbs are connected with $$5A$$ line
Explanation
In India, the voltage between two wires is $$220 V$$. So, C is wrong. All other statements are correct.
Magnetic field lines around straight wire is .....
Report Question
0%
parallel to the wire
0%
perpendicular to the wire
0%
circular
0%
elliptical
Explanation
Solution:
The magnetic field lines around a straight wire is in form of concentric circles with its center lying on the wire itself. The direction of these magnetic field lines can be found out using right hand thumb rule.
Answer:
Hence magnetic field lines around a straight wire is circular i.e, option
C
is correct.
A coil carries a current in a magnetic field. The coil experiences a turning effect. Which device uses this effect?
Report Question
0%
A d.c motor
0%
An electromagnet
0%
A relay
0%
A transformer
Explanation
A simple electric motor can be built using a coil of wire that is free to rotate between two opposite magnetic poles. When an electric current flows through the coil, the coil experiences a force and moves.
So, it must be a d.c. motor.
In faraday's experiment current in not produced in
Report Question
0%
the coil is moved and magnetic is stationary
0%
the magnetic is moved the coil is stationary
0%
both coil and magnetic are moved in same direction with same speed
0%
both coil and magnet stationary
Explanation
According to Faraday experiment: Emf will induced in the coil when the magnetic flux across the coil changes with time. In given conditions in options A and B, magnetic flux will change across the coil whereas, in C and D flux across the coil will not change so current will not produce.
Which device uses slip rings?
Report Question
0%
A d.c electric motor
0%
A relay
0%
A transformer
0%
An a.c. generator
Explanation
Slip rings are used in an AC Generator. It is
hollow rings that are connected to the ends of the armature coil and it helps to produce Ac current.
Write true or false for the following statements :
magnetic field due to a straight current-carrying conductor is in the form of concentric circles.
Report Question
0%
True
0%
False
Explanation
The pattern of magnetic field is like concentric circles around straight conductor according to right hand thumb rule or cork screw rule.
When a conductor carrying an electric current is free to move in a magnetic field, the direction in which it will move is given by:
Report Question
0%
Cork-screw rule
0%
Fleming's Left Hand rule
0%
Laplace's rule
0%
Swimming rule
Explanation
When current flows in a wire, and an external magnetic field is applied across that flow, the wire experiences a force perpendicular, to that field and to the direction of the current flow. Considering the figure, Fleming's left hand rule states that :
The thumb represents the direction of the thrust on the conductor /
M
otion of the Conductor.
The fore finger represents the direction of the magnetic field
The middle finger represents the direction of the current.
The laws of electromagnetic induction have been used in the construction of a :
Report Question
0%
Galvanometer
0%
Voltmeter
0%
Electric motor
0%
Electric generator
Explanation
Hint:
The laws of Electromagnetic Induction give us idea about the various ways in which we can produce Electric Current using Electric or Magnetic field.
Correct Option is D.
Explanation for correct answer:
$$\bullet $$ Galvanometer is a device which detects current in the circuit.
$$\bullet $$
Voltmeter is a device which measures potential difference between two point
s in the circuit.
$$\bullet $$
Electric motor is a device which converts Electrical Energy into Mechanical Energy.
$$\bullet $$
Electric Generator is an device which produces Electric Current from Mechanical energy, Chemical energy, or by using Magnetic or Electric Fields.
The laws if Electromagnetic Induction are used in Electric Generator which produces Electric Current from Magnetic or Electric Fields.
A circular loop, placed in a plane perpendicular to the plane of paper, carries a current when the key is ON. The current, as seen from points A and B (in the plane of the paper and on the axis of the coil) is anti-clockwise and clockwise respectively. The magnetic field lines point from B to A. The N-pole of the resultant magnet is on the face close to:
Report Question
0%
A
0%
B
0%
A if the current is small, and B if the current is large
0%
B if the current is small and A if the current is large
Explanation
From right hand thumb rule, it can be shown that magnetic lines of force emerge out from face close to A, and go into the face close to B.
Factually, the magnetic fields emerge from north pole of magnet, and go into the south pole. Hence the correct answer is option A.
An electron beam is moving from left to right of the observer and magnetic field is acting vertically upwards. The direction of force acting on electron is
Report Question
0%
towards the observer
0%
away from the observer
0%
downwards
0%
upwards
Explanation
From Flemings's left hand rule,
force on a positive charge moving from left to right and magnetic field being vertically upwards is towards the observer. If the charge is negative (example electron), force acts opposite to this direction i.e. away from the observer.
An $$\alpha $$-particle moves from east to west in a magnetic field perpendicular to the plane of the paper and into the paper. The particle is deflected towards:
Report Question
0%
East
0%
West
0%
South
0%
North
Explanation
An $$\alpha$$-particle is a positively charged particle. The direction of current is along the direction of motion of the $$\alpha$$-particle(east to west). The direction of the magnetic field is into the paper. Therefore,
by using Fleming’s left-hand
rule,
the force is directed into the page south. So, the particle will be deflected towards the south.
0:0:1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
0
Answered
0
Not Answered
0
Not Visited
Correct : 0
Incorrect : 0
Report Question
×
What's an issue?
Question is wrong
Answer is wrong
Other Reason
Want to elaborate a bit more? (optional)
Practice Class 10 Physics Quiz Questions and Answers
<
>
Support mcqexams.com by disabling your adblocker.
×
Please disable the adBlock and continue.
Thank you.
Reload page
