Mantles for gas lanterns contain thorium, because it forms an oxide that can survive being heated to incandescence for long periods of time. natural thorium is almost 100% 232th, with a half-life of 1.405 ✕ 1010 y. if an average lantern mantle contains 200 mg of thorium, what is its activity (in bq)?

The activity is 811.77 Bq

Solution:

As per the question:

Half life of Thorium,

Mass of Thorium, m = 200 mg = 0.2 g

M = 232 g/mol

Now,

No. of nuclei of Thorium in 200 mg of Thorium:

where

= Avagadro's number

Thus

Also,

Activity is given by:

b.transmitters send radio waves, and receivers capture radio waves.

find the sum of the two horizontal vectors and the sum of the two vertical vectors

isoceles right angled triangle