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Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of (11/3) Ω?
Concept: Kirchhoff’s Laws
Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of (11/5) Ω?
Concept: Kirchhoff’s Laws
Define the term 'electrical conductivity' of a metallic wire. Write its S.I. unit.
Concept: Specific Resistance
Show variation of resistivity of Si with temperature in a graph ?
Concept: Temperature Dependence of Resistance
A potentiometer wire of length 1.0 m has a resistance of 15 Ω. It is connected to a 5 V battery in series with a resistance of 5 Ω. Determine the emf of the primary cell which gives a balance point at 60 cm.
Concept: Cells, Emf, Internal Resistance
In the circuit shown in the figure, find the total resistance of the circuit and the current in the arm AD.
Concept: Ohm's Law
Three concentric metallic shells A, B and C or radii a, b and c (a < b < c) have surface charge densities + σ, −σ and + σ, respectively as shown in the figure
If shells A and C are at the same potential, then obtain the relation between the radii a, b and c.
Concept: Flow of Electric Charges in a Metallic Conductor
A cell of emf ‘E’ and internal resistance ‘r’ draws a current ‘I’. Write the relation between terminal voltage ‘V’ in terms of E, I and r ?
Concept: Cells, Emf, Internal Resistance
A heating element is marked 210 V, 630 W. What is the value of the current drawn by the element when connected to a 210 V dc source?
Concept: Resistivity of Various Materials
The emf of a cell is always greater than its terminal voltage. Why? Give reason.
Concept: Potential Difference and Emf of a Cell
A heating element is marked 210 V, 630 W. Find the resistance of the element when connected to a 210 V dc source.
Concept: Resistivity of Various Materials
Calculate the value of the resistance R in the circuit shown in the figure so that the current in the circuit is 0.2 A. What would b the potential difference between points B and E?
Concept: Kirchhoff’s Laws
Calculate the value of the resistance R in the circuit shown in the figure so that the current in the circuit is 0.2 A. What would b the potential difference between points A and B?
Concept: Kirchhoff’s Laws
In the given circuit, assuming point A to be at zero potential, use Kirchhoff’s rules to determine the potential at point B.
Concept: Kirchhoff’s Laws
Plot a graph showing the variation of stopping potential with the frequency of incident radiation for two different photosensitive materials having work functions W1 and W2 (W1 > W2). On what factors does the (i) slope and (ii) intercept of the lines depend?
Concept: Resistivity of Various Materials
A cell of emf ‘E’ and internal resistance ‘r’ is connected across a variable resistor ‘R’. Plot a graph showing the variation of terminal potential ‘V’ with resistance R. Predict from the graph the condition under which ‘V’ becomes equal to ‘E’.
Concept: Cells, Emf, Internal Resistance
Derive an expression for drift velocity of free electrons in a conductor in terms of relaxation time.
Concept: Drift of Electrons and the Origin of Resistivity
Obtain the expression for the current flowing through a conductor having number density of the electron n, area of cross-section A in terms of the drift velocity vd .
Concept: Drift of Electrons and the Origin of Resistivity
How does the resistivity of a semiconductor change with rise of temperature ? Explain.
Concept: Resistivity of Various Materials
Answer the following question.
How is the drift velocity in a conductor affected with the rise in temperature?
Concept: Concept of Electric Currents in Conductors
