Answer:
3 photons
Explanation:
The energy of a photon E can be calculated using this formula:

Where
corresponds to Plank constant (6.626070x10^-34Js),
is the speed of light in the vacuum (299792458m/s) and
is the wavelength of the photon(in this case 800nm).

Tranform the units

The band Gap is 4eV, divide the band gap between the energy of the photon:

Rounding to the next integrer: 3.
Three photons are the minimum to equal or exceed the band gap.
<span>At the periphery of a hurricane the air is sinking, and several kilometers above the surface, in the eye, the air is sinking. </span>
The adaptation that is genetic change or mutatiton help makes an organism to survive better in their new environment.
Answer:
4.96×10¯¹⁰ N
Explanation:
The following data were obtained from the question:
Mass 1 (M1) = 300 Kg
Mass 2 (M2) = 300 Kg
Separating distance (r) = 110 m
Gravitational constant (G) = 6.67×10¯¹¹ Nm²/Kg²
Gravitational force (F) =?
The gravitational force between the two goal posts can be obtained as follow:
F = GM1M2 / r²
F = 6.67×10¯¹¹ × 300 × 300 / 110²
F = 6.003×10¯⁶ / 12100
F = 4.96×10¯¹⁰ N
Therefore the gravitational force between the two goal posts is 4.96×10¯¹⁰ N
Answer:

Explanation:
The change in kinetic energy will be simply the difference between the final and initial kinetic energies: 
We know that the formula for the kinetic energy for an object is:

where <em>m </em>is the mass of the object and <em>v</em> its velocity.
For our case then we have:

Which for our values is:
