CBSE Class 10 Science Magnetic Effects of Electric Current Worksheet Set 03

MCQ Questions for NCERT Class 10 Science Magnetic Effects Of Electric Current 

Question. Consider the following statements and choose the correct are:
(a) A magnet is an object which attracts pieces of iron, Nickel and cobalt
(b) Magnetic effect of electric current means that an electric current flowing in a wire produces a magnetic field around it
(c) The end of a freely suspended magnet which points towards the north direction is called the north pole of the magnet
(d) All of the above

Answer: D

Question. Two wires are placed in parallel; repulsion force and current in these two wires are “f” and “i” respectively. What will be a force if the current is doubled in each wire ?
(a) 2f
(b) f/2
(c) 2f/4
(d) 4f

Answer: D

Question. The magnetic field inside a long straight solenoid-carrying current
(a) is zero.
(b) decreases as we move towards its end.
(c) increases as we move towards its end.
(d) is the same at all points.
Answer: D

Question. Which of the following property of a proton can change while it enters freely in a magnetic field? (There may be more than one correct answer.)
(a) mass
(b) speed
(c) velocity
(d) momentum
Answer : B

Question. The phenomenon of electromagnetic induction is:
(a) The process of charging a body
(b) The process of generating magnetic field due to a current passing through a coil
(c) Producing induced current in a coil to relative motion between a magnet and the coil
(d) The process of rotating a coil of an electric motor

Answer: C

Question. Mutual induction is a process in which current is induced in the neighbouring coil if current flows in a coil. In the figure shown below: 

(a) Maximum in situation (A)
(b) Maximum in situation (B)
(c) Maximum in situation (C)
(d) Same in all situation

Answer: A

Question. A charged particle enters at right angle into a uniform field as shown. What should be the nature of charge on the particle if it begins to move in a direction pointing vertically out of the page due to its interaction with the magnetic field?
(a) Positive
(b) Negative
(c) Natural
(d) Can't decide

Answer: A

Question. For the current in a long straight solenoid N- and S-poles are created at the two ends. Among the following statements, the incorrect statement is
(a) The field lines inside the solenoid are in the form of straight lines which indicates that the magnetic field is the same at all points inside the solenoid
(b) The strong magnetic field produced inside the solenoid can be used to magnetise a piece of magnetic material like soft iron core, when placed inside the coil
(c) The pattern of magnetic field associated with the solenoid is different from the pattern of the magnetic field around a bar magnet
(d) The N- and S-poles exchange positions when the direction of current through the solenoid is reversed
Answer : C

Question. A current flows in a wire, running between the S and N poles of a magnet lying horizontally as shown in the figure below: 

The force on the wire due the magnet is directed.
(a) From N to S
(b) From S to N
(c) Vertically downwards
(d) Vertically upwards

Answer: C

Question. A student learns that magnetic field strength around a bar magnet is different at every point which diagram shows the correct magnetic field lines around a bar magnet? 

Answer: D

Question. Which of the following is not true?
(a) Induction proceeds attractions
(b) We cannot isolate a single pole
(c) We can magnetic an iron ring
(d) A permanent magnet retains its magnetism even when heated on a flame

Answer: D

Question. A finite straight wire carries a current of 3 A, where it is a 2 m long and weighs around 240 g. If it is suspended in the mid-air by a uniform magnetic field then calculate the field B. [Acceleration due to gravity = 9.8 m/s2]
(a) 0.39 T
(b) 0.42 T
(c) 0.61 T
(d) 0.37 T

Answer: A

Question. Which of the following correctly describes the magnetic field near a long straight wire?
(a) The field consists of straight lines perpendicular to the wire
(b) The field consists of straight lines parallel to the wire
(c) The field consists of radial lines originating from the wire
(d) The field consists of concentric circles centred on the wire

Answer: D

Question. The phenomenon of electromagnetic induction is
(a) the process of charging a body
(b) the process of generating magnetic field due to a current passing through a coil
(c) producing induced current in a coil due to relative motion between a magnet and the coil
(d) the process of rotating a coil of an electric motor

Answer: C

Question. The device used for producing electric current is called a
(a) generator
(b) galvanometer
(c) ammeter
(d) motor

Answer: A

Question. The essential difference between an AC generator and a DC generator is that
(a) AC generator has an electromagnet while a DC generator has permanent magnet.
(b) DC generator will generate a higher voltage.
(c) AC generator will generate a higher voltage.
(d) AC generator has slip rings while the DC generator has a commutator.

Answer: D

Question. At the time of short circuit, the current in the circuit
(a) reduces substantially
(b) does not change
(c) increases heavily
(d) vary continuously

Answer: C

Question. The process of inducing a current in a coil of wire by placing it ina region of changing magnetic field is:
(a) Electrical effect
(b) Heating effect of current
(c) Magnetic effect of current
(d) Electromagnetic induction

Answer: D