Here is the answer to your question
Absolutely ! If you have two vectors with equal magnitudes and opposite
directions, then one of them is the negative of the other. Their correct
vector sum is zero, and that's exactly the magnitude of the resultant vector.
(Think of fifty football players pulling on each end of the rope in a tug-of-war.
Their forces are equal in magnitude but opposite in sign, and the flag that
hangs from the middle of the rope goes nowhere, because the resultant
force on it is zero.)
This gross, messy explanation is completely applicable when you're totaling up
the x-components or the y-components.
Answer: 
Explanation:
The Compton Shift 
in wavelength when the photons are scattered is given by the following equation:
(1)
Where:
is a constant whose value is given by 
, being 
the Planck constant, 
the mass of the electron and 
the speed of light in vacuum.
the angle between incident phhoton and the scatered photon.
We are told the maximum Compton shift in wavelength occurs when a photon isscattered through 
:
(2)
(3)
Now, let's find the angle that will produce a fourth of this maximum value found in (3):
(4)
(5)
If we want 
, 
must be equal to 1:
(6)
Finding 
:
Finally:
This is the scattering angle that will produce 
Renewable energy
<u>Advantages :-</u>
1. Easily regenerate
2. Boost economic growth
3. Easily available
4. Support environment
5. Low maintenance cost
<u>Disadvantages :-</u>
1. Weather dependency
2. High installation cost
3. Noise caused by wind energy
4. Fluctuation problem (solar)
5. Intermittency issue (wind)
Non-renewable energy
<u>Advantages :-</u>
1. Concentrated energy source
2. Reliable energy source
3. Can be built anywhere
4. No radioactive waste
<u>Disadvantages :-</u>
1. Produces greenhouse gases
2. Contributes to global warming
3. Produces acid rain
4. Harmful to environment when they are burnt
<em>I hope this helps.....</em>
To answer these questions just use the equations for potential energy using the mass and heights described. the potential energy at the prescribed heights = the initial kinetic energy required to reach that height.
Make sure you calculate the force of gravity on the surface using the radius of the planet.
