Answer:
2.63 x 10^18
Explanation:
A = 1 cm^2 = 1 x 10^-4 m^2
λ = 10,000 nm = 10,000 x 10^-9 m = 10^-5 m
T = 37 degree C = 37 + 273 = 310 k
Energy of each photon = h c / λ
where, h is the Plank's constant and c be the velocity of light
Energy of each photon = (6.63 x 10^-34 x 3 x 10^8) / 10^-5 = 1.989 x 10^-20 J
Energy radiated per unit time = σ A T^4
Where, σ is Stefan's constant
Energy radiated per unit time = 5.67 x 10^-8 x 10^-4 x 310^4 = 0.05236 J
Number of photons per second = Energy radiated per unit time / Energy of
each photon
Number of photons per second = 0.05236 / (1.989 x 10^-20) = 2.63 x 10^18
please, give the question properly.
Answer:
There is no friction between the card and the cup.
Explanation:
Answer:
Explanation:
Potential energy on the surface of the earth
= - GMm/ R
Potential at height h
= - GMm/ (R+h)
Potential difference
= GMm/ R - GMm/ (R+h)
= GMm ( 1/R - 1/ R+h )
= GMmh / R (R +h)
This will be the energy needed to launch an object from the surface of Earth to a height h above the surface.
Extra energy is needed to get the same object into orbit at height h
= Kinetic energy of the orbiting object at height h
= 1/2 x potential energy at height h
= 1/2 x GMm / ( R + h)
<span>A. three</span><span>
Oil spill can be very harmful to marine life because the chemical make up of oils can be poisonous to marine life. The oil can also affect the natural body temperature of marine animals especially to the small fish. Sea otters and sea birds are the most commonly affected by oil spills and those other marine animals that can be found in the shoreline. Heavy oils like the bunker oils used to fuel ships are the most harmful oil because when this oil stick to birds feathers, they may have an inability to warm themselves that could lead them to die.</span>
