Advertisements
Advertisements
Question
The figure given below shows three resistors?
Their combined resistance is:
(a) `1 5/7`Ω
(b) `14` Ω
(c) `6 2/3` Ω
(d) `7 1/2` Ω
Advertisements
Solution
(d) `7 1/2`Ω
The resistors of 6and 2 are connected in parallel
∴ `1/R=1/R_1+1/R_2`
Here,
`R_1=6`Ω
`R_2=2` Ω
`1/R=1/6+1/2`
`1/R=4/6`
`R=6/4`
This arrangement is further connected in series with the 6 resistor
∴Net resistance` =6/4+6=7 1/2` Ω
APPEARS IN
RELATED QUESTIONS
Complete the following :-
(b)
Several electric bulbs designed to be used on a 220 V electric supply line are rated 10 W. How many lamps can be connected in parallel with each other across the two wires of 220 V line if the maximum allowable current is 5 A?
A resistor has a resistance of 176 ohms. How many of these resistors should be connected in parallel so that their combination draws a current of 5 amperes from a 220 volt supply line?
A resistor of 8 ohms is connected in parallel with another resistor X. The resultant resistance of the combination is 4.8 ohms. What is the value of the resistor X?
How will you connect three resistors of 2 Ω, 3 Ω and 5 Ω respectively so as to obtain a resultant of 2.5 Ω? Draw the diagram to show the arrangement.
Two exactly similar electric lamps are arranged (i) in parallel, and (ii) in series. If the parallel and series combination of lamps are connected to 220 V supply line one by one, what will be the ratio of electric power consumed by them?
Calculate the equivalent resistance between the points A and B in Fig. if each resistance is 2·0 Ω.
A uniform wire with a resistance of 27 Ω is divided into three equal pieces and then they are joined in parallel. Find the equivalent resistance of the parallel combination.
Show how would you connect three resistors, each of resistance 6 O so that
the combination has a resistance of(a) 9 Ω (b) 4 .Ω
Two resistors of resistance 4 Ω and 6 Ω are connected in parallel to a cell to draw 0.5 A current from the cell.
Calculate current in each resistor.
An electrical appliance having a resistance of 200 Ω is operated at 200 V. Calculate the energy consumed by the appliance in 5 minutes in kWh.
The equivalent resistance of a parallel combination of two resistors of 30 Ω and 60 Ω is ______________.
Solve the following question:
In an electric circuit, two resistors of 12 0 each are joined in parallel to a 6 V battery. Find the current drawn from the battery.
What connection is used in domestic appliances and why?
Two devices are connected between two points say A and B in parallel. The physical quantity that will remain the same between the two points is:
Calculate the current flows through the 10 Ω resistor in the following circuit.
Two V-I graphs A and B for series and parallel combinations of two resistors are as shown. Giving reason state which graph shows (a) series, (b) parallel combination of the resistors.
Two resistors of resistance 2 Ω and 3 Ω are connected in parallel to a cell to draw current 0.5 A from the cell. Calculate the current in each resistor.
