The elongation of a wire on the surface of the earth is 10^$$-$$4 m. The same wire of same dimensions is elongated by 6 $$\times$$ 10^$$-$$5 m on another planet. The acceleration due to gravity on the planet will be ____________ ms^$$-$$2. (Take acceleration due to gravity on the surface of earth = 10 ms^$$-$$2)

A 10 $$\Omega$$, 20 mH coil carrying constant current is connected to a battery of 20 V through a switch. Now after switch is opened current becomes zero in 100 $$\mu$$s. The average e.m.f. induced in the coil is ____________ V.

A light ray is incident, at an incident angle $$\theta$$₁, on the system of tow plane mirrors M₁ and M₂ having an inclination angle 75$$^\circ$$ between them (as shown in figure). After reflecting from mirror M₁ it gets reflected back by the mirror M₂ with an angle of reflection 30$$^\circ$$. The total deviation of the ray will be _____________ degree.

In a vernier callipers, each cm on the main scale is divided into 20 equal parts. If tenth vernier scale division coincides with nineth main scale division. Then the value of vernier constant will be _________ $$\times$$ 10^$$-$$2 mm.