Two point charges of 10 C each are kept at a distance of 3 m in vacuum.Calculate their electrostatic potential energy.
Four capacitors C1, C2, C3 and C4 are connected as shown in the figure below. Calculate equivalent capacitance of the circuits between points X and Y.
Draw a labelled graphs to show how electrical resistance varies with temperature for:
i) a metallic wire
ii) a piece of carbon
Two resistors R1 = 400 ohm and R2 = 20 ohm are connected in parallel to a battery. If heating power developed in R1 is 25 W, find the heating power developed in R2.
With the help of a labelled diagram, show that the balancing condition of a wheatstone bridge is:
; have their usual meanings.
A 10 m long uniform metallic wire having a resistance 20 ohm is used as a potentiometer wire. This wire is connected in series with another resistance of 480 ohm and a battery of emf 5 V having negligible internal resistance.If an unknown emf e is balanced across 6 m of the potentiometer wire, calculate:
i) the potential gradient across the potentiometer wire.
ii) the value of the unknown emf e.
Given,
Length of wire, l = 10 m
Resistance, R = 20 ohm
EMF of battery = 5 V
i) IP =Â Â =Â
Potential gradient, k =Â
              =Â
              =Â
ii) Unknown emf, e =Â Â = 0.12 V
i) Explain the term hysteresis.
ii) Name the three elements of the earth's magnetic field which help in defining earth's magnetic field completely.
Obtain an expression for magnetic flux density B at the centre of a circular coil of radius R, having N turns and carrying a current I.
A coil of self inuctance 2.5 H and resistance 20 ohm is connected to a battery of emf 120 V having internal resistance of 5 ohm. Find:
i) the time constant of the circuit
ii) the current in the circuit in steady state.
In a series LCR circuit, what is the difference between VL and VC where vL is the potential difference across the inductor and VCis the potential difference across the capacitor.