Physics ICSE Class 7 Important Questions Chapter 7 Electricity and Magnetism
Additional Questions
A. Tick (√) the best option :
Question 1.
Natural magnet is obtained from mineral called.
(a) magnes
(b) magnetite
(c) magnesia
(d) magnetight
Answer:
(b) magnetite
Question 2.
Cobalt and nickel are
(a) magnetic materials
(b) non-magnetic material
(c) electrical materials
(d) none of these
Answer:
(a) magnetic materi als
Question 3.
Copper and silver are
(a) magnetic materials
(b) non-magnetic materials
(c) optical materials
(d) none of these
Answer:
(b) non-magnetic materials
Question 4.
When a magnet is suspended freely, it rests in direction called
(a) east-west direction
(b) east-north direction
(c) north-south direction
(d) west-south direction
Answer:
(c) north-south direction
Question 5.
Two like poles
(a) repel each other
(b) attract each other
(c) may repel or attract
(d) neither repel nor attract
Answer:
(a) repel each other
Question 6.
Magnetic poles exist as
(a) triplets
(b) independent monopoles
(c) quads
(d) pairs
Answer:
(d) pairs
Question 7.
Earth behaves like a
(a) non-magnet
(b) single piece of iron
(c) bar magnet
(d) U-magnet
Answer:
(c) bar magnet
Question 8.
A piece of iron can be turned into a magnet by
(a) single touch method
(b) double touch method
(c) electrical method
(d) all of these
Answer:
(d) all of these
Question 9.
Permanent magnet is made of
(a) steel
(b) soft iron
(c) steel and soft iron
(d) aluminium
Answer:
(a) steel
Question 10.
For safe storage of magnets, we use
(a) magnetic box
(b) non magnetic keepers
(c) magnetic keepers
(d) none of these
Answer:
(c) magnetic keepers
B. Tick (√) the best choice :
Question 1.
Substances that have property of attracting iron are called
(a) conductors
(b) insulators
(c) dielectric
(d) magnets
Answer:
(d) magnets
Question 2.
Materials attracted by a magnet are called
(a) magnetic substances
(b) plastic
(c) PVC
(d) nylon
Answer:
(a) magnetic substances
Question 3.
Examples of magnetic material is / are
(a) iron
(b) nickel
(c) cobalt
(d) all of these
Answer:
(d) all of these
Question 4.
When a magnet is suspended freely, it rest in –
(a) same direction
(b) any direction
(c) (a) or (b)
(d) none of these
Answer:
(d) none of these
C. Fill in the-blanks :
Question 5.
Sure test for a magnet is ………….
Answer:
Sure test for a magnet is repulsion.
Question 6.
Like poles ………….. each other.
Answer:
Like poles repel each other.
Question 7.
Scientist …………. found the direct relation between magnetism and electricity.
Answer:
Scientist Hans Christion Orsted found the direct relation between magnetism and electricity.
Question 8.
Electromagnets are used in loud speakers, electric bells and …………..
Answer:
Electromagnets are used in loud speakers, electric bells and electric motors.
Question 9.
Electric bell is based on the principle of
Answer:
Electric bell is based on the principle of electromagnetism.
D. Define
Question 10.
Circuit
Answer:
A loop of conducting wires and devices through which electric current flows is called an electric circuit.
Question 11.
Cell
Answer:
An electric cell transforms chemical energy into electrical energy by way of chemical reactions of chemicals stored in it.
Question 12.
Battery
Answer:
Group of cells is called battery.
Question 13.
Key
Answer:
A key is used to switch on or switch off a circuit.
Question 14.
Resistance ‘
Answer:
It is an opposition offered to the flow of current by a substance.
E. True or false :
Question 15.
Attraction is the sure test of magnetism.
Answer:
False.
Question 16.
Electromagnetism does not deal with electricity.
Answer:
False.
Question 17.
Current carrying conductor has magnetic effect around it.
Answer:
True.
Question 18.
Electromagnet is a permanent magnet.
Answer:
False.
Question 19.
Mechanical Bell works on electricity.
Answer:
False.
F. Fill in the blanks :
Question 20.
An electric bell has gong and …………..
Answer:
An electric bell has gong and hammer.
Question 21.
A battery generally consists of many cells in ……………
Answer:
A battery generally consists of many cells in series.
Question 22.
Electric current is flow of ……………
Answer:
Electric current is flow of electric charges.
Question 23.
…………… is opposition to electric current.
Answer:
Resistance is opposition to electric current.
Question 24.
Common electric source is dry .
Answer:
Common electric source is dry cell.
G. Match the following :
Answer:
ICSE Class 7 Physics Important Questions