A cyclotron is working at a frequency of 10 MHz. If the radius of its dees is 60 cm. The maximum kinetic energy of accelerated proton will be :

(Take : e = 1.6 $$\times$$ 10^$$-$$19 C, m_p = 1.67 $$\times$$ 10^$$-$$27 kg)

A hydrogen atom in ground state absorbs 12.09 eV of energy. The orbital angular momentum of the electron is increased by :

In the following nuclear reaction,

$$D\buildrel \alpha \over \longrightarrow {D_1}\buildrel {{\beta ^ - }} \over \longrightarrow {D_2}\buildrel \alpha \over \longrightarrow {D_3}\buildrel \gamma \over \longrightarrow {D_4}$$

Mass number of D is 182 and atomic number is 74. Mass number and atomic number of D₄ respectively will be _________.

The activity of a radioactive material is 2.56 $$\times$$ 10^$$-$$3 Ci. If the half life of the material is 5 days, after how many days the activity will become 2 $$\times$$ 10^$$-$$5 Ci ?