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

Distinguish between Step up and Step Down Transformer.

What is Transformer?

Explain step up and step down transformer?

The primary of a transformer has 40 turns and works on 100 V and 100 W. Find a number of turns in the secondary to step up the voltage to 400 V. Also calculate the current in the secondary and primary.

Describe the construction and working of a transformer with a neat labelled diagram.

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?