Nucleus — Physics STD 12 Science — Question

Light waves travel in vaccum along the y-axis. Then the wave front is:

Which of the following helps us in the determination of the temperature of sun(a) Kirchhoff's law(b) Maxwell Boltzmann law(c) Planck's law(d) Stefan's law

The separation between the plates of a charged parallel-plate capacitor is increased. Which of the following quantities will change?

1. Charge on the capacitor.
2. Potential difference across the capacitor.
3. Energy of the capacitor.
4. Energy density between the plates.

What happens to the wavelength of a photon after it collides with an electron?

Distance of communication satellite from the surface of the earth :

In hydrogen atom, if the difference in the energy of the electron in n = 2  and n = 3  orbits is E, the ionization energy of hydrogen atom is (a) 13.2 E(b) 7.2 E(c) 5.6 E  (d) 3.2 E

The critical mass of a fissionable material is:

A positively charged particle projected towards east is deflected towards north by a magnetic field. The field may be:

The mass number of a nucleus is equal to the number of(a) Electrons it contains(b) Protons it contains(c) Neutrons it contains(d) Nucleons it contains