Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

Can the potential energy in a simple harmonic motion be negative? Will it be so if we choose zero potential energy at some point other than the mean position?

A car travels at a speed of 60km/hr due north and the other at a speed of 60km/hr due east. Are the velocities equal? If no, which one is greater? If you find any of the questions irrelevant, explain.

The speeds of red light and yellow light are exactly same:

1. In vacuum but not in air.
2. In air but not in vacuum.
3. In vacuum as well as in air.
4. Neither in vacuum nor in air.

Write any two drawbacks of Rutherford's experiment related to atomic structure.

In a semiconductor the concentration of electrons is 8 × 10¹³ cm^–3 and that of holes is 5 × 10¹² cm^–3. Is it a p-type or n-type semiconductor?

A diverging lens of focal length 20cm and a converging mirror of focal length 10cm are placed coaxially at a separation of 5cm. Where should an object be placed so that a real image is formed at the object itself?

The sun is less bright at morning and evening as compared to at noon although its distance from the observer is almost the same. Why?

The X-ray coming from a Coolidge tube has a cutoff wavelength of 80pm. Find the kinetic energy of the electrons hitting the target.