Rules of counting#!#P&C

Significants Figures|Rules For Counting Significant Figures|Rounding Off|Remembering Technique

Fundamental Principle of Counting

The official counting of population is known as :

A counter gives a count of 320 counts/minute for a radioactive source . After 75 minutes, the counter shows a count rate of 40 counts/minute . What is the half life period of the source ?

Plane Mirror|| Counting OF Images

Perimeter of a triangle is found by using the formula P = a + b + c where a, b and c are the sides of the triangle. Write the rule that is expressed by this formula in words.

If p divisions on the venier scale of vernier calipers correspond to q main scale divisions (p gt q) , derive an expression ofr the least count of the instrument in terms of p and q. If 1 M.S.D. = k mm, express the least count in cm.

A pure radio-chemical preparation was observed to disintegrate at the rate of 2140 counts/minutes at 12.35 P.M. of the same day, the disintegration rate of the sample was only 535 count/minutes. What is the half-life of the material?