Advertisements
Advertisements
प्रश्न
Two resistances R and 2R are connected in parallel in an electric circuit. The thermal energy developed in R and 2R are in the ratio _______________ .
विकल्प
1 : 2
2 : 1
1 : 4
4 : 1
उत्तर
2 : 1
Thermal energy developed in the resistances,
H = \[\frac{V^2}{R}t\]
Heat developed in the resistance R, H1= \[\frac{V^2}{R}t\]
Heat developed in the resistance 2R, H2 = \[\frac{V^2}{2R}t\]
Thus, Heat developed in the resistance R and 2R are in ratio 2 : 1.
APPEARS IN
संबंधित प्रश्न
Three resistors 1 Ω, 2 Ω, and 3 Ω are combined in series. What is the total resistance of the combination?
Two resistors R1 = 400Ω and R2 = 20 n are connected in parallel to a battery. If heating the power developed in R1 is 25 W. find the heating power developed in R2
Suppose you have three resistors of 20 Ω, 50 Ω and 100 Ω. What minimum and maximum resistance can you obtain from these resistors?
If the reading of the ammeter, A1 in the following figure is 2.4 A, what will be the readings of ammeters A2 and A3? Neglect the resistances of the ammeters.
An ideal battery sends a current of 5 A in a resistor. When another resistor of 10 Ω is connected in parallel, the current through the battery is increased to 6 A. Find the resistance of the first resistor.
Find the equivalent resistance of the circuits shown in the figure between the points a and b. Each resistor has resistance r.
Find the current measured by the ammeter in the circuit shown in the figure.
An ammeter is to be constructed that can read currents up to 2.0 A. If the coil has resistance of 25 Ω and takes 1 mA for full-scale deflection, what should be the resistance of the shunt used?
Two voltameters, one with a solution of silver salt and the other with a trivalent-metal salt, are connected in series and a current of 2 A is maintained for 1.50 hours. It is found that 1.00 g of the trivalent metal is deposited. (a) What is the atomic weight of the trivalent metal?
(b) How much silver is deposited during this period? Atomic weight of silver is 107.9 g mol−1.
Two resistors R1= 60 Ω and R2 = 90Ω are connected in parallel. If electric power consumed by the resistor R1 is15 W, calculate the power consumed by the resistor R2.
In parallel combination of n cells, we obtain ______.
If two resistors of resistances R1 = (4 ± 0.5) Ω and R2 = (16 ± 0.5) Ω are connected in series. The eqivalent resistance with the limits of percentage error is ______.
The effective resistance of a parallel connection that consists of four wires of equal length, equal area of cross-section and the same material is 0.25 Ω. What will be the effective resistance if they are connected in series?
An electric cable of copper has just one wire of radius 9 mm. Its resistance is 14Ω. If this single copper wire of the cable is replaced by seven identical well insulated copper wires each of radius 3 mm connected in parallel, then the new resistance of the combination will be:
Eight identical cells, each of emf 2V and internal resistance 3 Ω, are connected in series to form a row. Six such rows are connected in parallel to form a battery. This battery is now connected to an external resistor R of resistance 6 Ω. Calculate:
- emf of the battery.
- internal resistance of the battery.
- current flowing through R.
Three bulbs B1 (230V, 40W), B2 (230V, 60W) and B3 (230V, 100W) are connected in series to a 230V supply. Which bulb glows the brightest?