Advertisements
Advertisements
Question
A student carries out an experiment and plots the V-I graph of three samples of nichrome wire with resistances R1, R2 and R3 respectively. Which of the following is true?
Options
R1 = R2 = R3
R1 > R2 > R3
R3 > R2 > R1
R2 > R3 > R1
Advertisements
Solution
R3 > R2 > R1
Explanation -
Since the current (I) is plotted on y-axis and potential difference (V) is plotted on x-axis, so the slope of the graph is `1/"R"`. It means higher the slope, the lesser is the resistance. So, R1 will be minimum and R3 will be maximum.
APPEARS IN
RELATED QUESTIONS
If the potential difference across the ends of a conductor is 220 V and the resistance of the conductor is 44 Ω (ohm), then the current flowing through is _________.
- 0.2 A
- 0.5 A
- 2 A
- 5 A
Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?
Write the formula of resistivity
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
A wire of resistance 9 ohm having length 30 cm is tripled on itself. What is its new resistance?
What length of copper wire of resistivity 1.7 × 10-8 Ω m and radius 1 mm is required so that its resistance is 2Ω?
How would you connect two resistors in series? Draw a diagram. Calculate the total equivalent resistance.
A wire has a length of 2.0 m and a resistance of 5.0 Ω. Find the electric field existing inside the wire if it carries a current of 10 A.
How does an increase in the temperature affect the specific resistance of a semiconductor?
Fig. represents the circuit used for the verification of ohm's law. Label the different parts from A and F. State the function of each.
- Name and state the law which relates the potential difference and current in a conductor.
- What is the necessary condition for a conductor to obey the law named above in part (a) ?
State the relation correlating the electric current flowing in a conductor and the voltage applied across it. Also, draw a graph to show this relationship.
Ohm’s law states the relationship between power and voltage.
What is ohmic device?
An electronics hobbyist is building a radio which requires 150 Ω in her circuit, but she has only 220 Ω, 79 Ω, and 92 Ω resistors available. How can she connect the available resistors to get the desired value of resistance?
The circuit depicted in the figure is employed for studying Ohm’s Law. Instead of using a standard resistor, a student opts for a glass tube filled with mercury (tube 1), connected to the circuit through two electrodes, E1 and E2. He records the readings of the ammeter and voltmeter, thereby calculating the resistance. The student repeats the experiment by substituting tube 1 with tube 2, where the same amount of mercury fills tube 2.
Neglecting internal resistance of the cell use (> or < or =) to compare:
- the resistance in both the cases.
- the voltmeter readings in both the cases.
- the specific resistance in both the cases.
From Ohm's Law, since \[I \propto V\], the constant ratio \[\frac{V}{I}\] is defined as:
If a current of 1 A flows through a conductor, then according to Ohm's Law, the resistance of the conductor is:
Which of the following is an example of a Non-Ohmic material?
What is the nature of the graph obtained when potential difference is plotted against current for an Ohmic conductor?
