Answer:
The answer is below
Explanation:
Using Coulomb's law of electric field which is:


Answer:
Its ok but the answer is C
Explanation:
Answer:
<em>The wavelength of water = 571.43 nm</em>
Explanation:
Refractive index of water = wave length of light in air/wave length of light in water
R.d = λ₁/λ₂.................. Equation 1
making λ₂ the subject of equation 1
λ₂ = λ₁/R.d...................... Equation 2
R.d = refractive index of water , λ₁ = wave length of light in air, λ₂ = wave length of light in water
<em>Given: R.d = 1.33, λ₁ = 760nm</em>
<em>Substituting these values into equation 2</em>
λ₂ = 760/1.33
<em>λ₂ = 571.43 nm</em>
<em>Therefore the wavelength of water = 571.43 nm</em>
Answer:
3
Explanation:
The half-life is the time it takes for the amount of radioactive isotope to halve. Therefore, we have:
- After 1 half-life, only 1/2 of the element will be left
- After 2 half-lives, only 1/4 of the element will be left
- After 3 half-lives, only 1/8 of the element will be left
So, it will take 3 half-lives for the element to become 1/8 of its original amount.
Mathematically, this can be also verified by using the equation

where
N(t) is the amount of the element left at time t
N0 is the initial amount of the element
is the half-life
Substituting
(3 half-lives), we find
