1
JEE Main 2017 (Online) 8th April Morning Slot
+4
-1
There is a uniform electrostatic field in a region. The potential at various points on a small sphere centred at $$P,$$ in the region, is found to vary between the limits 589.0 V to 589.8 V. What is the potential at a point on the sphere whose radius vector makes an angle of 60o with the direction of the field ?
A
589.5 V
B
589.2 V
C
589.4 V
D
589.6 V
2
JEE Main 2017 (Online) 8th April Morning Slot
+4
-1
The energy stored in the electric field produced by a metal sphere is 4.5 J. If the sphere contains 4 $$\mu$$C charge, its radius will be :
[ Take : $${1 \over {4\,\pi { \in _0}}} =$$ 9 $$\times$$ 109 N $$-$$ m2/C2 ]
A
20 mm
B
32 mm
C
28 mm
D
16 mm
3
JEE Main 2017 (Offline)
+4
-1
An electric dipole has a fixed dipole moment $$\overrightarrow p$$, which makes angle $$\theta$$ with respect to x-axis. When subjected to an electric field $$\mathop {{E_1}}\limits^ \to = E\widehat i$$ , it experiences a torque $$\overrightarrow {{T_1}} = \tau \widehat k$$ . When subjected to another electric field $$\mathop {{E_2}}\limits^ \to = \sqrt 3 {E_1}\widehat j$$ it experiences a torque $$\mathop {{T_2}}\limits^ \to = \mathop { - {T_1}}\limits^ \to$$ . The angle $$\theta$$ is:
A
90o
B
45o
C
30o
D
60o
4
JEE Main 2016 (Online) 10th April Morning Slot
+4
-1
Within a spherical charge distribution of charge density $$\rho$$(r), N equipotential surfaces of potential V0, V0 + $$\Delta$$V, V0 + 2$$\Delta$$V, .......... V0 + N$$\Delta$$V ($$\Delta$$ V > 0), are drawn and have increasing radii r0, r1, r2,..........rN, respectively. If the difference in the radii of the surfaces is constant for all values of V0 and $$\Delta$$V then :
A
$$\rho$$ (r) $$\alpha$$ r
B
$$\rho$$ (r) = constant
C
$$\rho$$ (r) $$\alpha$$ $${1 \over r}$$
D
$$\rho$$ (r) $$\alpha$$ $${1 \over {{r^2}}}$$
JEE Main Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
Chemistry
Physical Chemistry
Inorganic Chemistry
Organic Chemistry
Mathematics
Algebra
Trigonometry
Coordinate Geometry
Calculus
EXAM MAP
Joint Entrance Examination