1
JEE Advanced 2016 Paper 2 Offline
+3
-0
Consider an evacuated cylindrical chamber of height h having rigid conducting plates at the ends and an insulating curved surface as shown in the figure. A number of spherical balls made of a light weight and soft material and coated with a conducting material are placed on the bottom plate. The balls have a radius r << h. Now, a high voltage source (HV) connected across the conducting plates such that the bottom plate is at +V0 and the top plate at $$-$$V0. Due to their conducting surface, the balls will get charge, will become equipotential with the plate and are repelled by it. The balls will eventually collide with the top plate, where the coefficient of restitution can be taken to be zero due to the soft nature of the material of the balls. The electric field in the chamber can be considered to be that of a parallel plate capacitor. Assume that there are no collisions between the balls and the interaction between them is negligible. (Ignore gravity)

Which one of the following statement is correct?
A
The balls will execute simple harmonic motion between the two plates
B
The balls will bounce back to the bottom plate carrying the same charge they went up with
C
The balls will stick to the top plate and remain there
D
The balls will bounce back to the bottom plate carrying the opposite charge they went up with
2
JEE Advanced 2016 Paper 2 Offline
+3
-0
Consider an evacuated cylindrical chamber of height h having rigid conducting plates at the ends and an insulating curved surface as shown in the figure. A number of spherical balls made of a light weight and soft material and coated with a conducting material are placed on the bottom plate. The balls have a radius r << h. Now, a high voltage source (HV) connected across the conducting plates such that the bottom plate is at +V0 and the top plate at $$-$$V0. Due to their conducting surface, the balls will get charge, will become equipotential with the plate and are repelled by it. The balls will eventually collide with the top plate, where the coefficient of restitution can be taken to be zero due to the soft nature of the material of the balls. The electric field in the chamber can be considered to be that of a parallel plate capacitor. Assume that there are no collisions between the balls and the interaction between them is negligible. (Ignore gravity)

The average current in the steady state registered by the ammeter in the circuit will be
A
proportional to $$V_0^2$$
B
proportional to the potential $${V_0}$$
C
zero
D
proportions to $$V_0^{1/2}$$
3
JEE Advanced 2014 Paper 2 Offline
+3
-1
Charges $$Q,$$ $$2Q$$ and $$4Q$$ are uniformly distributed in three dielectric solid spheres $$1,2$$ and $$3$$ of radii $$R/2,R$$ and $$2R$$ respectively, as shown in figure. If magnitude of the electric fields at point $$P$$ at a distance $$R$$ from the center of sphere $$1,2$$ and $$3$$ are $${E_1}$$, $${E_2}$$ and $${E_3}$$ respectively, then

A
$${E_1} > {E_2} > {E_3}$$
B
$${E_3} > {E_1} > {E_2}$$
C
$${E_2} > {E_1} > {E_3}$$
D
$${E_3} > {E_2} > {E_1}$$
4
JEE Advanced 2014 Paper 2 Offline
+3
-1

Four charges Q1, Q2, Q3 and Q4 of same magnitude are fixed along the x axis at x = $$-$$2a, $$-$$a, +a and +2a, respectively. A positive charge q is placed on the positive y axis at a distance b > 0. Four options of the signs of these charges are given in List I. The direction of the forces on the charge q is given in List II. Match List I with List II and select the correct answer using the code given below the lists.

List I List II
P. Q$$_1$$, Q$$_2$$, Q$$_3$$, Q$$_4$$ all positive 1. +x
Q. Q$$_1$$, Q$$_2$$ positive; Q$$_3$$, Q$$_4$$ negative 2. $$-$$x
R. Q$$_1$$, Q$$_4$$ positive; Q$$_2$$, Q$$_3$$ negative 3. +y
S. Q$$_1$$, Q$$_3$$ positive; Q$$_2$$, Q$$_4$$ negative 4. $$-$$y

A
P-3, Q-1, R-4, S-2
B
P-4, Q-2, R-3, S-1
C
P-3, Q-1, R-2, S-4
D
P-4, Q-2, R-1, S-3
EXAM MAP
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