1. ⇒ (MHT CET 2023 13th May Morning Shift )

Which of the following statements is 'WRONG' for the conductors?

A. In static situation, the interior of conductor can have no charge.

B. The net electrostatic field is zero in the interior of a conductor.

C. The electrostatic field just outside the surface of charged conductor must be tangential to the surface at any point.

D. The electrostatic potential is constant within and on the surface of a conductor.

Correct Option is (C)

The electric field just outside the surface of the conductor is perpendicular to the surface which is a property of conductors in electrostatic equilibrium.

2. ⇒ (MHT CET 2023 13th May Morning Shift )

If the magnitude of intensity of electric field at a distance ' $r_{1}$ ' on an axial line and at a distance ' $r_{2}$ ' on an equatorial line due to a given short dipole are equal, then $r_{1} : r_{2}$ , is

A. $\sqrt[3]{2} : 1$

B. $\sqrt{2} : 1$

C. $1 : 2$

D. $1 : \sqrt[3]{2}$

Correct Option is (A)

$\begin{aligned} E_{axial} = E_{equatorial} \Rightarrow k \frac{2 p}{r_{1}^{3}} = \frac{k p}{r_{2}^{3}} \\ \Rightarrow \frac{r_{1}}{r_{2}} = \frac{2^{1 / 3}}{1} = \sqrt[3]{2} : 1 \end{aligned}$

3. ⇒ (MHT CET 2023 12th May Evening Shift )

Select the correct statement from the following.

A. Gravitational force is stronger than electrostatic force

B. Gravitational as well as electrostatic force always attractive.

C. Gravitational as well as electrostatic force always act along the line joining the two objects.

D. Inverse square law $(F \propto \frac{1}{r^{2}})$ is not obeyed by electrostatic force.

Correct Option is (C)

Currently no explanation available

4. ⇒ (MHT CET 2023 12th May Morning Shift )

Two electric dipoles of moment $P$ and $27 P$ are placed on a line with their centres $24 cm$ apart. Their dipole moments are in opposite direction. At which point the electric field will be zero between the dipoles from the centre of dipole of moment P?

A. 6 cm

B. 8 cm

C. 10 cm

D. 12 cm

Correct Option is (A)

Dipole of moment p is at a distance x from N

MHT CET 2023 12th May Morning Shift Physics - Electrostatics Question 6 English Explanation

At N, |E. F. due to dipole 1| = |E. F. due to dipole 2|

$\begin{aligned} ∴ \frac{1}{4 π ε_{0}} \cdot \frac{2 p}{x^{3}} = \frac{1}{4 π ε_{0}} \cdot \frac{2 (27 p)}{(24 - x)^{3}} \\ ∴ \frac{1}{x^{3}} = \frac{27}{(24 - x)^{3}} \Rightarrow x = 6 cm . \end{aligned}$

5. ⇒ (MHT CET 2023 11th May Evening Shift )

An electron of mass ' $m$ ' and charge ' $q$ ' is accelerated from rest in a uniform electric field of strength ' $E$ '. The velocity acquired by the electron, when it travels a distance ' $L$ ', is

A. $\sqrt{\frac{2 q m}{mL}}$

B. $\sqrt{\frac{2 qEL}{m}}$

C. $\sqrt{\frac{2 Em}{qL}}$

D. $\sqrt{\frac{qE}{mL}}$

Correct Option is (B)

We know

$\begin{aligned} F = m a and F = q E \\ qE = ma \\ ∴ & \frac{qE}{m} = a \end{aligned}$

According to equation of motion,

$\begin{aligned} v^{2} - u^{2} = 2 a L \\ v^{2} - 0^{2} = 2 a L \\ v^{2} = 2 a L \\ v = \sqrt{2 a L} \\ ∴ & v = \sqrt{\frac{2 q E L}{m}} \end{aligned}$

⇒Electrostatics