Thermionic Emission and Radioactivity — Physics STD 10 — Question

A flat coil ABCD is freely suspended between the pole pieces of a U-shaped permanent magnet with the plane of coil parallel to the magnetic field.

Name an instrument which makes use of the principle stated above.

State the approximate range of wavelength associated with the ultraviolet rays .

What determines the frequency of a.c. produced in a generator?

A mixture of radioactive substance gives off three types of radiation name the radiation which is deviated most in a magnetic field.

Define the term intensity of a sound wave. State the unit in which it is measured.

Classify the following into lever as class I, class II or class III of a fishing rod ?

It is advised not to touch a radioactive substance by hand. Give reason.

What is the order of current drawn by appliances connected to the ‘light circuit’ of a household?

Why is the loudness of the sound heard by a plucked wire increased when it is mounted on a sound board?

How will rise in sea level affect population in coastal countries?