A astronomical telescope has objective and eye-piece of focal lengths
A astronomical telescope has objective and eye-piece of focal lengths 40 cm, 4 cm, respectively. To view an object 200…
7 years ago
Physics
A person can see clearly objects only when they lie between 50 cm and 400 cm from
A person can see clearly objects only when they lie between 50 cm and 400 cm from his eyes. In…
7 years ago
The frequency of a light wave in a material is 2 x 10¹⁴ Hz and wavelength is 5000Å.
The frequency of a light wave in a material is 2 x 10¹⁴ Hz and wavelength is 5000Å. The refractive…
7 years ago
A radioactive nucleus of mass M emits a photon of frequency v and the nucleus recoils.
A radioactive nucleus of mass M emits a photon of frequency v and the nucleus recoils. The recoil energy will…
7 years ago
The radioactivity of a certain material drops to 1/16 of the initial value in 2 hours.
The radioactivity of a certain material drops to 1/16 of the initial value in 2 hours. The half-life of this…
7 years ago
Which one of the following statements is true, if half-life of a radioactive substance
Which one of the following statements is true, if half-life of a radioactive substance is 1 month? Options (a) 7/8th…
7 years ago
₉₂U²³⁵ undergoes successive disintegrations with the end product of ₈₂P²⁰³
₉₂U²³⁵ undergoes successive disintegrations with the end product of ₈₂P²⁰³. The number of α and β-particles emitted are Options (a)…
7 years ago
A radioactive sample S₁ having an activity of 5 μCi has twice the number of nuclei
A radioactive sample S₁ having an activity of 5 μCi has twice the number of nuclei as another sample S₂…
7 years ago
The half-life period of a radio-active element X is same as the mean life time
The half-life period of a radio-active element X is same as the mean life time of another radio-active element Y.…
7 years ago
In gamma ray emission from a nucleus
In gamma ray emission from a nucleus Options (a) only the proton number changes (b) both the neutron number and…
7 years ago