HSC Science (Electronics) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions for Physics

In Hydrogen, the electron jumps from the fourth orbit to the second orbit. The wavenumber of the radiations emitted by an electron is ______  

The decay constant λ of a certain radioactive material is 0.2166 per day. The average life τ of the radioactive material is ______ 

The half-life of a certain radioactive species is 6.93 × 10⁵ seconds. What is the decay constant?  

Show that half life period of radioactive material varies inversely to decay constant λ.

The half-life of a certain radioactive nucleus is 3.2 days. Calculate (i) decay constant (ii) average life of radioactive nucleus.

Show that for radioactive decay N(t) = `"N"_"O" "e"^{-λ"t"}`, where symbols have their usual meaning.

Obtain an expression for the half-lifetime of radioactive material. Hence state the relation between an average life and half life time of radioactive material.

A radioactive substance decays to (1/10)^th of its original value in 56 days. Calculate its decay constant. 

What is alpha decay?

What is beta decay?

A 0.1 H inductor a 25 × 10^-6 F capacitor and a 15 Ω resistor are connected in series to a 120 V, 50 Hz AC source. Calculate the resonant frequency.

If ‘θ’ represents the angle of contact made by a liquid which completely wets the surface of the container then ______.

The disintegration rate of a radio-active sample is 10¹⁰ per hour at 20 hours from the start. It reduces to 5 × 10⁹ per hour after 30 hours. Calculate the decay constant.

From the v - t graph of a particle executing SHM of period T, which following statements is INCORRECT?

If the number of nuclei of a radioactive substance becomes `1/e` times the initial number in 10 days, what is the decay constant of the substance?

Show that the number of nuclei of a radioactive material decreases exponentially with time.

Efficiency of transformer is the ratio of ______.

The half-life of \[\ce{^238_92U}\] undergoing ∝- -decay is 4.5 × 10⁹ years. What is the activity of 1g sample of \[\ce{^238_92U}\]?

Prove that the inductance of parallel wires of length l in the same circuit is given by L = `((mu_0l)/pi) "in" (d/a)` where 'a' is the radius of wire and d is seperation between wire axes.

Define half-life period.