# Introduction to Computer

Topics: Electric charge, Electric potential, Magnetic field Pages: 3 (408 words) Published: November 13, 2012
CBSE TEST PAPER-05 CLASS - XII PHYSICS (Unit – Electrostatics)

1.

The Plates of a charged capacitor are connected by a voltmeter. If the plates of the capacitor are moved further apart. What will be the effect on the reading of the voltmeter?

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2. 3.

What is the function of dielectric in a capacitor? A steam of electrons travelling with speed υ m s at right angles to a uniform e v2 = ? m rE

[1] [2]

electric field E is deflected in a circular path of radius r. Prove that 4.

The distance between the plates of a parallel plate capacitor is d. A metal plate of thickness (d/2) is placed between the plates. What will be the effect on the capacitance?

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5.

Keeping the voltage of the charging source constant. What would be the percentage change in the energy stored in a parallel plate capacitor if the separation between its plates were to be decreased by 10%?

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6.

Two identical plane metallic surfaces A and B are kept parallel to each other in air separated by a distance of 1.0 cm as shown in the figure. Surface A is given a positive potential of 10V and the outer surface of B is earthed. (a) What is the magnitude and direction of uniform electric field between point Y and Z? What is the work done in moving a change of 20 µ c from point X to Y? (b) Can we have non-zero electric potential in the space, where electric field strength is zero?

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B A X Z

Y

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7.

Figure (a) and (b) shows the field lines of a single positive and negative changes respectively

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(a) Give the signs of the potential difference : Vp − Vq and VB -- VA (b) Give the sign of the work done by the field in moving a small positive change from Q to P. (c) Give the sign of the work done by the field in external agency in moving a small negative change from B to A.

8.

With the help of a...