If both waves have the same wavelength, then the amplitude of
their sum could be anything between 1 cm and 9 cm, depending
on the phase angle between them.
If the waves have different wavelengths, then the resultant is a beat
with an amplitude of 9 cm.
Answer:
Explanation:
<u></u>
<u>1. Formulae:</u>
Where:
- E = kinetic energy of the particle
- λ = de-Broglie wavelength
- m = mass of the particle
- v = speed of the particle
- h = Planck constant
<u><em>2. Reasoning</em></u>
An alha particle contains 2 neutrons and 2 protons, thus its mass number is 4.
A proton has mass number 1.
Thus, the relative masses of an alpha particle and a proton are:

For the kinetic energies you find:


Thus:


From de-Broglie equation, λ = h/(mv)

Answer:
Explanation:
Gravitational Potential Energy at earth surface 
Gravitational Potential Energy at height h is 
Energy required to lift the satellite 

Now Energy required to orbit around the earth



(given)




(b)For greater height
is greater than 
thus energy to lift the satellite is more than orbiting around earth
Answer:
a) 0.0288 grams
b) 
Explanation:
Given that:
A typical human body contains about 3.0 grams of Potassium per kilogram of body mass
The abundance for the three isotopes are:
Potassium-39, Potassium-40, and Potassium-41 with abundances are 93.26%, 0.012% and 6.728% respectively.
a)
Thus; a person with a mass of 80 kg will posses = 80 × 3 = 240 grams of potassium.
However, the amount of potassium that is present in such person is :
0.012% × 240 grams
= 0.012/100 × 240 grams
= 0.0288 grams
b)
the effective dose (in Sieverts) per year due to Potassium-40 in an 80- kg body is calculate as follows:
First the Dose in (Gy) = 
= 
= 
Effective dose (Sv) = RBE × Dose in Gy
Effective dose (Sv) = 
Effective dose (Sv) = 