Answer:
A. 28 years
Explanation:
Applying,
R = R'(2ᵃ/ⁿ).............. Equation 1
Where R = Original sample, R' = Sample left after decay, a = Total time taken to decay, n = half life.
From the question,
Given: R = 12 g, R' = 6 g, a = 28 years.
Substitute into equation 1 and solve for n
12 = 6(2²⁸/ⁿ)
12/6 = 2²⁸/ⁿ
2²⁸/ⁿ = 2
Equation the base,
28/n = 1
n = 28 years.
Hence the half-life is 28 years
For example, consider the energy used by an electric fan. The amount of electrical energy used is greater than the kinetic energy of the moving fan blades. Because energy is always conserved, some of the electrical energy flowing into the fan's motor is obviously changed into unusable or unwanted forms.
Answer:
wavelength = 2.81 m
Explanation:
Given that,
The frequency of the Sports Fan radio station, f = 106.4 MHz
We need to find the wavelength (in meters) of the electromagnetic carrier wave. The relation between frequency and wavelength is given by :
Where,
is wavelength
So, the wavelength of the electromagnetic carrier wave is 2.81 m.
If you increase the volume the pressure will decrease. so the best answer is C
