Electric Charges and Fields — Physics STD 12 Science — Question

The horizontal component of the earth's magnetic field at a place is B and angle of dip is 60°.What is the value of vertical component of earth's magnetic field at equator?

A light ray is incident perpendicularly on a plane mirror. What will be the values of angle of incidence and angle of reflection?

If on converting galvanometer of resistance G into ammeter, 1% of main current passes through the galvanometer, then what is the resistance of the shunt?

What are the directions of electric and magnetic field vectors relative to each other and relative to the direction of propagation of electromagnetic waves?

What is a mass unit?

A steel rod of cross-sectional area 4cm² and length 2m shrinks by 0.1cm as the temperature decreases in night. If the rod is clamped at both ends during the day hours, find the tension developed in it during night hours. Young's modulus of steel = 1.9 × 10¹¹N/m².

Which of the following has the minimum wavelength and which has the maximum wavelength?
Blue light, infrared rays, gamma rays, green light.

NaCl molecule is bound due to the electric force between the sodium and the chlorine ions when one electron. of sodium is transferred to chlorine. Taking the separation between the ions to be 2.75 × 10cm, find the force of attraction between them· State the assumptions (if any) that you have made.

Two proton beams going in the same direction repel each other whereas two wires carrying currents in the same direction attract each other. Explain.