Advertisements
Advertisements
Question
Calculate the effective resistance across AB?
Advertisements
Solution
5 Ω and 4Ω are in series
∴ R1 = (5 + 4)Ω = 9Ω
Now, 9Ω and 3Ω are in parallel
`therefore R_2 = (9 xx 3)/(9+3)=9/4Ω`
Now, 2 8Ω and R2 are in series
`therefore R_3 = 8 +9/4 =41/4 Ω= 10.25Ω`
APPEARS IN
RELATED QUESTIONS
Graph showing the variation of current versus voltage for a material Ga As is shown in the figure. Identify the region of
(i) negative resistance
(ii) where Ohm's law is obeyed.
Keeping the p.d. constant, the resistance of a circuit is halved. The current will become:
(a) one-fourth
(b) four time
(c) half
(d) double
Four resistances of 16 ohms each are connected in parallel. Four such combinations are connected in series. What is the total resistance?
A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination of resistances in half a minute.
In an experiment of verification of Ohm’s law following observations are obtained.
|
Potential difference V (in volt) |
0.5 | 1.0 | 1.5 | 2.0 | 2.5 |
| current I (in ampere) | 0.2 | 0.4 | 0.6 | 0.8 | 1.0 |
Draw a V-I graph and use this graph to find:
- the potential difference V when the current I is 0.5 A,
- the current I when the potential difference V is 0.75 V,
- the resistance in a circuit.
How does an increase in the temperature affect the specific resistance of a :
(i) Metal and
(ii) Semiconductor ?
What is non-ohmic resistor?
Calculate the total resistance of the circuit and find the total current in the circuit.
The heat produced by a 100 w heater in 2 minute is equal to
Suppose there is a circuit consisting of only resistances and batteries and we have to double (or increase it to n-times) all voltages and all resistances. Show that currents are unaltered. Do this for circuit of Example 3.7 in the NCERT Text Book for Class XII.
