**CBSE HOT Physics Questions for Class 12th Board Exam 2013****, given here.**

Magnetic needle is deviated 30°C from meridian at a plan. If observed dip angle is 45°C. Find actual dip angle.

A point P lies at 10 cm at ∏ /4 angle from short dipole. find direction of B from magnetic dipole at ―"P" that is angle of B and M

Two magnetic dipole P and Q of magnetic dipole moment M1 and M2 are suspended at a place by two thread of same material .When their point of suspension are rotated 240°C and 270°C. Each magnet deflects through 30°C from meridian. Find M1/M2?.

Show that in the free oscillations of an LC circuit, the sum of energies stored in the capacitor and the inductor is constant in time.

Using the Rydberg formula, calculate the wavelengths of the first four spectral lines in the Lyman series of the hydrogen spectrum.

How an AM wave is detected? Draw the necessary block diagram. Why is modulation necessary for transmission?

What is Van de Graff generator? Explain its principle, construction and working with the help of diagram. What is the maximum possible potential which can be generated by it?