1.
Two electric bulbs marked 25W – 220V and 100W – 220V are connected in series to a 440Vsupply. Which of the bulbs will fuse?
Answer: Option 'B'
Resistances of both the bulbs are R1=V^2/P1 = 220^2/25 R2 = V^2/P2 = 220^2/100 Hence R1gt ; R2R1gt ; R2 When connected in series, the voltages divide in them in the ratio of their resistances. The voltage of 440 V devides in such a way that voltage across 25 w bulb will be more than 220 V. Hence 25 w bulb will fuse.
2.
It is more difficult to walk on ice than on a concrete road because
3.
Which of the following is not a vector quantity
4.
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5.
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6.
The speed of light will be minimum while passing through
7.
It is more difficult to walk on ice than on a concrete road because
8.
A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will
9.
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