English

An electromagnet does not attract a piece of iron.

Advertisements
Advertisements

Question

An electromagnet does not attract a piece of iron.

Options

  • True

  • False

MCQ
True or False
Advertisements

Solution

This statement is False.

Explanation:

  • The working of an electromagnet is based on the magnetic effect of electric current.
  • When current passes through it, an electromagnet behaves as a magnet, attracting a piece of iron.
shaalaa.com
  Is there an error in this question or solution?
Chapter 10: Electric Current and Its Effects - Exercises [Page 120]

APPEARS IN

NCERT Science [English] Class 7
Chapter 10 Electric Current and Its Effects
Exercises | Q 9. (c) | Page 120

RELATED QUESTIONS

Will the compass needle show deflection when the switch in the circuit shown by figure is closed?


When the switch S is closed in the figure given below, the pointer of the galvanometer moves to the right.  

 

If S is kept closed, will the pointer:

(a) return to zero?
(b) stay over on the right?
(c) move to the left and stay there
(d) move to and fro until S is opened


A coil is connected to a galvanometer. When the N-pole of magnet is pushed into the coil, the galvanometer deflected to the right. What deflection, if any, is observed when:  

 the N-pole is removed?




A coil is connected to a galvanometer. When the N-pole of magnet is pushed into the coil, the galvanometer deflected to the right. What deflection, if any, is observed when: 

 the S-pole is inserted?


What is the function of a split ring in an electric motor?


Observe the following diagram and choose the correct alternative:


(c) Considering the relationship in the first pair, complete the second paie :
AgCI : White :: CuI2 : ___________


Answer the following question:
State the effect on the magnetic needle in Oersted’s experiment when:  
(a) the current is passed through the wire.  
(b) the current through the wire is increased
(c) the current through the wire is reversed. 


Read the given passage and answer the following questions:

The home electrical connection consists of ‘live’, ‘neutral’ and ‘earth’ wires. The ‘live’ and the ‘neutral’ wires have potential difference of 220 V. The ‘earth’ is connected to ground. Due to a fault in the equipment or if the plastic coating on the ‘live’ and the ‘neutral’ wires gives a way the two wires come in contact with each other and a large current flows through it producing heat. If any inflammable material (such as wood, cloth, plastic, etc.) exists around that place it can catch fire. Therefore a fuse wire is used as a precautionary measure.

  1. Name the two wires having potential difference of 220 V.
  2. What is a short circuit?
  3. Write the function of a fuse.

Explain the magnetic field created by a current around a conductor from the figure.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×