Half-life of a radioactive substance is the time required to reduce the amount of substance to half of its initial amount.
In present case, half-life is material is given as 1000 years and initial amount of material is given as 400 kg
Answer 1) Since, half-life of radio-active substance is 1000 years, therefore after 1st half life, amount of the material will be left to half the initial amount. Hence, amount of substance left after 1000 years = 400/2 = 200 kg.
Answer 2) For 2000 years, radioactive material has crossed 2 times the half life. Therefore , amount of the material will be left to 1/4 the initial amount. Hence, amount of substance left after 2000 years = 400/4 = 100 kg.
Answer 3) For 4000 years, radioactive material has crossed 4 times the half life. Therefore , amount of the material will be left to 1/16 the initial amount. Hence, amount of substance left after 4000 years = 400/16 = 25 kg.
Explanation:
Given that,
Mass number, A = 302
Atomic number, Z = 119
We know that, atomic number = no of protons
Protons = 119
Mass no. = No. of neutrons + No. of protons
302 = No. of neutrons + 119
No. of neutrons = 302 - 119
= 183
No. of electrons = No. of protons
= 119
<span>Definition of Metallurgy-The branch of science and technology concerned with the properties of metals and their production and purification.</span>
Answer:
Hm creo que es La carcasa es de titanio y la batería está compuesta de acumuladores de litio y yodo, que pueden durar cerca de diez años. Los electrodos que lo componen pueden ser de distintos tipos, pero sus puntas, que no están aisladas, son de platino, y el número de los mismos dependerá de las necesidades de cada paciente
Explanation:
