Class 10 Exam  >  Class 10 Notes  >  Science Class 10  >  Short & Long Answer Questions: Magnetic Effects of Electric Current

Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current

Q1: Define a solenoid. Compare the magnetic field produced by a solenoid with that of a bar magnet?
Ans: A coil of many circular turns of wire wrapped in the shape of a cylinder, is called a solenoid. The magnetic field lines in a solenoid, through which current is passed, is very similar to that of a bar magnet. One end of the coil acts like a magnetic north pole, while the other acts like a south pole. The magnetic field produced by a long solenoid has all the properties of the field produced by a bar magnet.
Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current
Q2: PQ is conductor × represents magnetic is ⊥ to the paper field and into the plane of the paper. 
Ans: Fleming’s left-hand rule gives the direction of force experienced by a current-carrying conductor kept in a magnetic field. According to it, when the thumb, first finger and second finger of the left hand are kept perpendicular to each other such that the first finger points towards the direction of magnetic field, the central finger is along the direction of current, then the thumb shows the direction of the force acting on the conductor.

Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current

Q3:  Define Electromotive force.
Ans: The motion of a magnet, with respect to the coil, produces an induced potential difference. This induced potential difference is called electromotive force which sets up an induced electric current in the circuit. The motion of a magnet, with respect to the coil, produces an induced potential difference.

Q4: What is meant by earthing? Why should electrical appliances be earthed? 
Ans: The metal body of appliances like fridge, cooler, mixer etc. are connected to a an earth wire so that any leakage of current to the body of the appliance goes to the earth and does not give electric shock. This is called earthing. It is used as a safety measure in order to prevent electric shocks to the users.

Q5: What is a solenoid?
Ans: A solenoid is a long cylindrical conductor coil, having a large number of turns of insulated copper wire.

Q6 What is a magnetic field?
Ans: The region around a magnet, in which the magnetic force of attraction and repulsion is felt, is called a magnetic field.

Q7: Distinguish between a solenoid and a bar magnet. Draw the magnetic lines for both
Ans:

Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric CurrentThe solenoid is a long coil containing a large number of close turns of insulated copper wire. The magnetic field produced by the current carrying solenoid is similar to the magnetic field produced by a bar magnet. A solenoid is used for making electromagnets.Differences between a bar magnet and solenoid:
Bar magnet
It is a permanent magnet.
The strength of a bar magnet cannot be changed.
The polarity (North-South) of a bar magnet cannot be changed.
Solenoid
It is a temporary magnet. It acts as a magnet only as long as the current passes through it.
The strength of a solenoid can be changed by changing the number of turns in its coil or by changing the current passing through it.
The polarity of a solenoid can be changed by changing the direction of current in its coil.

Q8: What is electromagnetic induction? Explain how the movement of a magnet towards or away from a coil carrying a galvanometer produce current? Write the rule to find the direction of current in this above coil.
Ans: Whenever the magnetic field through a conductor changes, and induced current and e. m. f. is set up in the conductor. This is known as electromagnetic induction.

Electromagnetic induction is a process where a conductor placed in a changing magnetic field causes the production of a voltage across the conductor.

The rule being applied is Fleming's right-hand rule. Fleming’s right-hand rule is used to determine the direction of current induced in a coil due to its rotation in a magnetic field. When the magnet is moved towards the coil, there is a change in the magnetic field which induces a current in the coil. The same thing will happen when the magnet is moved away.

Q9: Which effect of electric current is utilized in the working of an electric fuse?
Ans: An electric fuse works on the heating effect of current.

Q10: Name an instrument in which the directive property of a magnet is used.
Ans: Compass needle makes use of the directive property of a magnet.

Q11: Name the elements of Earth’s magnetic field.
Ans: The elements of Earth’s magnetic field are angle of dip, declination and horizontal component of earth’s magnetic field.

Q12: Explain why, two magnetic lines of force do not intersect.
Ans: The magnetic lines of force do not intersect one another due to the fact that the resultant force on a north pole at any point can be only in one direction. But if the two magnetic lines of force intersect one another, then the resultant force on a north pole placed at the point of intersection will be along directions, which is not possible.

Q13: State the right-hand thumb rule.
Ans:Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric CurrentIf you hold the thumb, the forefinger and the centre finger of your right hand at right angles to one another. Adjust you hand in such a way that forefinger points in the direction of magnetic field, and the thumb points in the direction of motion of conductor, then the direction in which centre finger points, gives the direction of induced current in the conductor.

Q14: What is galvanometer?
Ans:

  • A galvanometer is an instrument that can detect the presence of a current in a circuit.
  • The pointer remains at zero (the centre of the scale) for zero current flowing through it.
  • It can deflect either to the left or to the right of the zero mark depending on the direction of current.

Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current

Q15: What is the role of fuse, used in series with any electrical appliance? Why should a fuse with defined rating not be replaced by one with larger rating?
Ans:
Fuse is used for protecting appliances due to short-circuiting or overloading. The fuse is rated for a certain maximum current and blows off when a current more than the rated value flows through it. If a fuse is replaced by one with larger ratings, the appliances may get damaged while the protecting fuse does not burn off. This practice of using fuse of improper rating should always be avoided.

The document Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current is a part of the Class 10 Course Science Class 10.
All you need of Class 10 at this link: Class 10
85 videos|437 docs|75 tests

Top Courses for Class 10

FAQs on Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current

1. What are the magnetic effects of electric current?
Ans. The magnetic effects of electric current refer to the phenomenon where a magnetic field is generated around a conductor when an electric current flows through it. This effect is utilized in various applications, such as electromagnets, electric motors, and transformers.
2. How can we demonstrate the magnetic field around a current-carrying conductor?
Ans. We can demonstrate the magnetic field around a current-carrying conductor using a simple experiment with a straight wire and a compass. When the current flows through the wire, the compass needle will deflect, indicating the presence of a magnetic field. The direction of the magnetic field can be determined using the right-hand thumb rule.
3. What is the right-hand thumb rule in relation to magnetic fields?
Ans. The right-hand thumb rule is a method used to determine the direction of the magnetic field around a current-carrying conductor. According to this rule, if you hold the conductor with your right hand such that your thumb points in the direction of the current, then your curled fingers will indicate the direction of the magnetic field lines around the conductor.
4. What are the applications of magnetic effects of electric current in real life?
Ans. The magnetic effects of electric current have several practical applications, including the functioning of electric motors (which convert electrical energy into mechanical energy), generators (which convert mechanical energy into electrical energy), transformers (which transfer electrical energy between circuits), and electromagnets (used in cranes and magnetic locks).
5. What is the difference between a permanent magnet and an electromagnet?
Ans. A permanent magnet is made from materials that produce a persistent magnetic field without the need for an external power source. In contrast, an electromagnet is created by passing an electric current through a coil of wire, generating a magnetic field that can be turned on or off by controlling the current. Electromagnets are often used in applications where adjustable magnetism is required.
85 videos|437 docs|75 tests
Download as PDF
Explore Courses for Class 10 exam

Top Courses for Class 10

Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Related Searches

Important questions

,

Objective type Questions

,

study material

,

Extra Questions

,

shortcuts and tricks

,

Semester Notes

,

Sample Paper

,

Viva Questions

,

ppt

,

video lectures

,

MCQs

,

Free

,

past year papers

,

Summary

,

Previous Year Questions with Solutions

,

pdf

,

Exam

,

Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current

,

mock tests for examination

,

Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current

,

Class 10 Science Chapter 12 Question Answers - Magnetic Effects of Electric Current

,

practice quizzes

;