<u>Answer</u>
1/4
<u>Explanation</u>
half life = 15 years
decay period = 30 years
The number of half-lives = 30 ÷ 15
= 2 half lives
1 ⇒(<em>after 1st half life</em>) ⇒ 1/2 ⇒ (<em>after 2nd half life</em>) ⇒ 1/4
The fraction that remained is 1/4.
Answer:
<em>Life science is alternatively known as biology, and physical science is subdivided into branches: physics, chemistry, Earth science, and astronomy.</em>
Answer:
Difference: The weak force tears an atomic nucleus apart.The strong force is what keeps the protons and neutrons in a nucleus held together, while the weak force is what makes radioactive particles decay.Or even simpler: The strong force keeps stuff together while the weak force helps stuff split up.
Similarities: Weak force allows quarks to turn into other quarks, which can turn a neutron into a proton and break up the nucleus. ... One big difference is that the particles/fields that are responsible for carrying the strong force are massless, whereas for the weak force they are quite massive (nearly 100 times the proton mass).
You have to draw a mathematical spatial axes .in order to judge is it right or not .. well you have to draw the crest and trough both of 1 cm in length and the total wavelength (same phase on the wave of 2 cm ) something like this