By the law of universal gravitation, the gravitational force <em>F</em> between the satellite (mass <em>m</em>) and planet (mass <em>M</em>) is
<em>F</em> = <em>G</em> <em>M</em> <em>m</em> / <em>R </em>²
where
<em>• G</em> = 6.67 × 10⁻¹¹ m³/(kg•s²) is the universal gravitation constant
• <em>R</em> = 2500 km + 5000 km = 7500 km is the distance between the satellite and the center of the planet
Solve for <em>M</em> :
<em>M</em> = <em>F R</em> ² / (<em>G</em> <em>m</em>)
<em>M</em> = ((3 × 10⁴ N) (75 × 10⁵ m)²) / (<em>G</em> (6 × 10³ kg))
<em>M</em> ≈ 2.8 × 10¹⁴ kg
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.
The observable universe consists of galaxies and other matter that can, principally, be seen from Earth because the light signals have had time to reach us. Not everything in the sky is the way it is when we see it, because of the distance the light travels to reach us.
Hope this helps :)
Answer:
0.752 m/s
Explanation:
m1 = 3.00kg
u1 = 5.05m/s
m2 = 2.76kg
u2 = -3.66m/s
According to the law of conservation of momentum,
m1u1 + m2u2 = (m1+m2)v
3(5.05) + 2.76(-3.66) = (5.05+2.76)v
15.15 - 9.2736 = 7.81v
5.8764 = 7.81v
v = 5.8764/7.81
v = 0.752m/s
