C is the answer because he wants to know if less force is needed to pull on a slippery surface which reduces friction
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Answer:</h3>
4.227 × 10^-19 Joules
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Explanation:</h3>
Energy of a photon of light is calculated by the formula;
E = hf, where h is the plank's constant, 6.626 × 10^-34 J-s and f is the frequency.
But, f = c/λ
Where, c is the speed of light (2.998 × 10⁸ m/s), and λ is the wavelength.
Given the wavelength is 470 nm or 4.7 × 10^-7 m
Therefore;
E = hc/λ
= (6.626 × 10^-34 J-s × 2.998 × 10^8 m/s) ÷ 4.7 × 10^-7 m
= 4.227 × 10^-19 Joules
Therefore, the energy of a photon with 470 nm is 4.227 × 10^-19 Joules
Atomic mass . . . ..........
Answer:
Explanation: As with any substance, oxygen takes up much less space as a liquid than it does as a gas, so engineers can fit more oxygen into the same tank.
