Question 1: Palette 1/9

BITSAT 2024 MCQ

An oil drop of radius $ 1 \mu \mathrm{~m} $ is held stationary under a constant electric field of $ 3.65 \times 10^{4} \mathrm{~N} / \mathrm{C} $ due to some excess electrons presence on it. If the density of oil drop is $ 1.26 \mathrm{~g} / \mathrm{cm}^{3} $, then number of excess electrons on the oil drop approximately are [Take, $ g=10 \mathrm{~ms}^{-2} $ ]

A

7

B

12

C

9

D

8

Question 2: Palette 2/9

BITSAT 2024 MCQ

The potential of a large liquid drop when eight liquid drops are combined is 20 V , then the potential of each single drop was

A

10 V

B

7.5 V

C

5 V

D

2.5 V

Question 3: Palette 3/9

BITSAT 2024 MCQ

A dust particle of mass $ 4 \times 10^{-12} \mathrm{mg} $ in suspended in air under the influence of an electric field of $ 50 \mathrm{~N} / \mathrm{C} $ directed vertically upwards. How many electrons were removed from the neutral dust particle? [Take, $ g=10 \mathrm{~m} / \mathrm{s} $ $ { }^{2} $ ]

A

15

B

8

C

5

D

4

Question 4: Palette 4/9

BITSAT 2024 MCQ

Electric field at point $ (30,30,0) $ due to a charge of $ 0.008 \mu \mathrm{C} $ placed at origin will be, (coordinates are in cm )

A

$ 8000 \mathrm{NC}^{-1} $

B

$ 4000(\hat{\mathbf{i}}+\hat{\mathbf{j}}) \mathrm{NC}^{-1} $

C

$ 200 \sqrt{2}(\hat{\mathbf{i}}+\hat{\mathbf{j}}) \mathrm{NC}^{-1} $

D

$ 400 \sqrt{2}(\hat{\mathbf{i}}+\hat{\mathbf{j}}) \mathrm{NC}^{-1} $

Question 5: Palette 5/9

BITSAT 2022 MCQ

Which one of the following graphs represents the variation of electric potential with distance r from the centre of a non-conducting charged sphere of radius R?

A

B

C

D

Question 6: Palette 6/9

BITSAT 2021 MCQ

Four charges equal to + Q are placed at the four corners of a square and a charge ($-$q) is at its centre. If the system is in equilibrium, then the value of $-$q is

A

$ - {Q \over 4}(1 + 2\sqrt 2 )$

B

${Q \over 2}(2\sqrt 2 + 1)$

C

${Q \over 4}(1 + 2\sqrt 2 )$

D

${Q \over 4}(1 + \sqrt 2 )$

Question 7: Palette 7/9

BITSAT 2021 MCQ

An electric dipole is placed at an angle of 30$^\circ$ in a non-uniform electric field. The dipole will experience

A

torque only

B

translational force only in the direction of the field

C

translational force only in a direction normal to the direction of the field

D

torque as well as a translational force

Question 8: Palette 8/9

BITSAT 2020 MCQ

A charge +q is placed at the origin O of XY-axes as shown in the figure. The work done in taking a charge Q from A to B along the straight line AB is

A

${{qQ} \over {4\pi {\varepsilon _0}}}\left( {{{a - b} \over {ab}}} \right)$

B

${{qQ} \over {4\pi {\varepsilon _0}}}\left( {{{b - a} \over {ab}}} \right)$

C

${{qQ} \over {4\pi {\varepsilon _0}}}\left( {{b \over {{a^2}}} - {1 \over b}} \right)$

D

${{qQ} \over {4\pi {\varepsilon _0}}}\left( {{a \over {{b^2}}} - {1 \over b}} \right)$

Question 9: Palette 9/9

BITSAT 2020 MCQ

Two small conducting spheres of equal radius have charges +20 $\mu$ C and $-$40 $\mu$C respectively and placed at a distance R from each other experience for F₁. If they are brought in contact and separated to the same distance, they experience force F₂. The ratio of F₁ to F₂ is

A

1 : 4

B

+8 : 1

C

$-$8 : 1

D

1 : 8