Advertisements
Advertisements
प्रश्न
Give one example to show how the resistance depends on the nature of material of the conductor.
Advertisements
उत्तर
APPEARS IN
संबंधित प्रश्न
Find the expression for resistors connected in series.
(i) Two sets A and B, of three bulbs each, are glowing in two separate rooms. When one of the bulbs in set A is fused, the other two bulbs also cease to glow. But in set B, when one bulb fuses, the other two bulbs continue to glow. Explain why this phenomenon occurs.
(ii) Why do we prefer arrangements of Set B for house circuiting?
An electrical appliance has a resistance of 25 Ω. When this electrical appliance is connected to a 230 V supply line, the current passing through it will be:
(a) 0.92 A
(b) 2.9 A
(c) 9.2 A
(d) 92 A
V = IRTwo resistances X and Y are connected turn by turn : (i) in parallel, and (ii) series. In which case the resultant resistance will be less than either of the individual resistances?R = R1+ R2+ R3
You are supplied with a number of 100 Ω resistors. How could you combine some of these resistors to make a 250 Ω resistor?
State how are the two resistors joined with a battery when same current flows in each resistor.
A graph is plotted taking p.d. along y-axis and electric current along x-axis. Name the physical quantity that represents the slope of this graph (Fig.).
Name the following substances:
(i) Showing low resistivity,
(ii) Showing very high resistivity,
(iii) Showing moderate resistivity.
How will you oonnect five resistors, each of the value one ohm, to obtain an equivalent resistance of 0.2 `Omega`
Choose the correct alternative and rewrite the following:
You are given three equal resistances. In how many combinations can they are arranged?
Answer the following question.
While studying the dependence of potential difference ( V) across a resistor on the current (I) passing through it, in order to determine the resistance of the resistor, a student took 5 readings for different values of current and plotted a graph between V and t. He got a straight line graph passing through the origin. What does the straight-line signify? Write the method of determining the resistance of the resister using this graph.
How does the resistance of an alloy, vary with temperature?
Six resistances are connected together as shown in the figure. Calculate the equivalent resistance between points A and B.
Two lamps of resistance 30Ω and 20Ω respectively are connected in series in a 110V circuit. Calculate:
(i) the total resistance in the circuit
(ii) the current in the circuit, and
(iii) the voltage drop across each lamp.
Two resistors of 4Ω and 6Ω are connected in parallel to a cell to draw 0.5 A current from the cell. Calculate the current in each resistor.
Two resistors having 2Ω and 3Ω resistance are connected—(i) in series, and (ii) in parallel. Find the equivalent resistance in each case.
The resistance of two resistors joined in series is 8Ω and in parallel is 1.5Ω. Find the value of the two resistances.
