Power Current Electricity ASGN 5 3 3 6 3 9 3 15 24

Prof. Yogesh Jahagirdar’s
Academy of Physics
Power
Current Electricity ASGN 5
1. In the given circuit power dissipated in 30 Ω resistance is
a) 10 W
b) 7.5 W
c) 5 W
d) 2.5 W
1
30 Ω
10 Ω
20 V
2. In adjacent figure, the power dissipated in 60 Ω
resistance is
a) 15 W
b) 30 W
2A
c) 7.5 W
d) 10 Ω
20 Ω
60 Ω
3. Power dissipated in 6Ω is 1.5 W. Power dissipated in 24 Ω is
32
W
9
96
W
c)
3
a)
b)
d)
32
18 Ω
W
3
13
W
3
24 Ω
6Ω
3
4. Power dissipated in 9 Ω resistance is
1
W
2
3
c) W
2
a)
1
W
4
3
d) W
4
6
3
b)
60 V
15
24
3
3
18
9
5. A 10W, 200 V and 20W, 200 V bulbs are connected in series across 200 V supply.
The total power dissipated is
a) 3.33 W
b) 4.56 W
c) 6.66 W
d) 30 W
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Prof. Yogesh Jahagirdar’s
Academy of Physics
Power
Current Electricity ASGN 5
2
6. Two bulbs rated as 60 W and 40 W, are connected is series across a voltage source.
The ratio of power dissipated in them is
d) 3 : 2
a) 2 : 3
b) 3 : 2
c) 2 : 3
7. Power dissipated in a wire connected to a cottage source is P. When the wire is
stretched to thrice its length, and connected to same voltage source, the power
dissipated in it will be
a) 3P
b) P/3
c) 9 P
d) P/9
8. 25 bulbs are connected in series across a voltage source. The illumination produced
is I. Now 3 bulbs are fused and they are removed. The remaining bulbs are
connected to same voltage source The illumination will
a) increase
b) decrease
c)remain same
d) become zero
9. Power dissipated in an uniform wire is P when connected to a voltage source. The
wire is now divided into 5 equal parts, and these are connected in parallel across
same voltage source . The power dissipated will now be
a) 5 P
b) P/5
c) 25 P
d) P/25
10. A coil made up of 4 resistances is shown in the figure. The coil is immersed is a box
containing ice. How much ice will melt in time t? (Latent heat of ice is L)
i2 R t
a)
L
i2 R t
b)
3L
3 i2 R t
c)
2 L
2 i2 R t
d)
3L
11. It takes 10 min to bal water in a kettle. If the length of the heating element is
doubled, how will it take to boil same amount of water?
a) 5 min
b) 10 min
c) 20 min
d) 40 min
www.cetphysics.in
phone no: 64533010
For test series:
www.diametrics.in
Prof. Yogesh Jahagirdar’s
Academy of Physics
Power
Current Electricity ASGN 5
3
12. An electrical kettle has 2 coils. With first coil, water is boiled in 15 min and with
second it is boiled in 30 min. When both coils are connected in series, the time
taken to boil the water will be
a) 10 min
b) 20 min
c) 35 min
d) 45 min
13. An electrical kettle has 2 coils. With fist coil, water is boiled in 15 min and with
second it is boiled in 30 min. When both coils are connected in parallel, the time
taken to boil the water will be
a) 10 min
b) 20 min
c) 35 min
d) 45 min
14. The voltage across a bulbs decreases by 3% .The power dissipated by bulb will
change by
a) 6%
b) 3%
c) – 6%
d) – 3%
15. A metal wire and a silicon wire are connected in left and left gap of a meter
bridge. The null point is obtained at the centre of the wire. The current is allowed to
flow through the wires for a long time. It is observed that null point will
a) Shift to left
b) Shift to right
c) remain at the centre
d) not be obtained
www.cetphysics.in
phone no: 64533010
For test series:
www.diametrics.in