Problem solving tips
3 min read

Electricity

- Want to score better marks in exams? Have a look at some problem solving tips
1

Tip 1

When solving combination network-based problems, segregate sections of the network which are in series connection and those in parallel. Identify primary networks and then identify the secondary branches For example, in the given circuit,
, and are in parallel.
As is in series with the rest, we can say
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If four resistances are connected as shown in the fig. between A and B, the effective resistance is:
A
B
C
D
The resistance between A and B in the given figure will be(in ohm):
A
20
B
30
C
90
D
more than 10 but less than 20
2

Tip 2

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A wire of 9 ohm resistance having 30 cm length is tripled on itself. What is its new resistance?
A
B
C
D
3

Tip 3

Memorizing one expression is enough. One can deduce the other ones by using Ohm's Law.
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An electric heater of resistance is run for  on a line of . The energy liberated in this period of time is:
A
B
C
D