Question 1 :
An electromagnets magnetic field can be rapidly manipulated over a wide range by controlling the amount of electric current supplied to the electromagnet. <br/>State whether the above statement is true or not?
Question 3 :
Choose the statement which is not correct in the case of an electric fuse.
Question 5 :
When the switch of an electric bell is on then electric current in it :<br/>
Question 8 :
$\text{Assertion(A)} :$ However long a fuse wire may be,the safe current that can be allowed is the same.<br/>$\text{Reason (R)} :$ The safe current that can be allowed to pass through a fuse wire depends on the radius of the wire.<br/>
Question 9 :
Complete the following sentences :A fuse wire is made of an alloy of .......... and ..........
Question 11 :
Match the following<table class="wysiwyg-table"><tbody><tr><td>1. Horse-shoe magnet</td><td>a. Holds the armature in place</td></tr><tr><td>2. Armature</td><td>b. Electromagnet</td></tr><tr><td>3. Spring strip</td><td>c. Passes electric current to the spring strip</td></tr><tr><td>4. Adjusting screw</td><td>d. Fixed to the spring strip</td></tr></tbody></table>
Question 13 :
What is the problem when a multi-plugs adaptor is used to connect many appliances to the same socket?<br>
Question 17 :
Which process is applied on a circuit for the working of an electric bell?
Question 19 :
Assertion: In its rest position the clapper is held away from the bell a short distance by its springy arm.
Reason: The spring constant of spring must be such that clapper should be able to give reaction to the magnetic force of attraction upto a certain extent
Question 23 :
Assertion: Fuse wire must have high resistance and low melting point.
Reason: Fuse is used for small current flow only.
Question 24 :
A 5 amp fuse wire can withstand a maximum power of 1 W in circuit. The resistance of the fuse wire is
Question 25 :
Why the applications of permanent magnet in the field ofengineering are quite limited?
Question 26 :
What will happen if the strip in a doorbell loses its flexibility?
Question 30 :
Two fuse wires of same length are rated 5 A and 20 A. Which is the correct?
Question 31 :
In which of the following situations will a fuse possibly melt?
Question 32 :
What specifications would you select for the material to make a fuse wire?<br/>
Question 33 :
What is the reason for the fuse and switch to be located at the<i>live</i>wire?
Question 34 :
If the current in a circuit rises too high, the fuse wire will ?<br/>
Question 35 :
Mark True if the statement is true and False if it is false:<br>When the electric current through the fuse exceeds a certain limit, the fuse wire melts and breaks.<br>
Question 37 :
Two identical fuses are rated at 10A. If they are joined<br><br>
Question 38 :
The rating of a fuse connected in the general householdlighting circuitis:
Question 39 :
Two fuse wires of the same length are rated 5 A and 20 A.Which of the fuse wires is thicker and why ?
Question 40 :
Assertion: Fuse wire must have high resistance and low melting point.
Reason: Fuse is used for small current flow only.