The answer of this question is
A.kg
(a) Intensity obeys inverse square law from basis of light passing through a given surface.
(b) Gravitation obeys inverse square law from the basis of force between two masses.
(c) The maximum magnitude of the acceleration of the block is 126.75 m/s².
<h3>
What is intensity?</h3>
Intensity is the ratio is ratio of power to area of a given surface.
I = P/A (W/m²)
where;
<h3>Universal gravitation law</h3>

Intensity and gravitation do not obey inverse square law for same reason;
- Intensity obeys inverse square law from basis of light passing through a given surface.
- Gravitation obeys inverse square law from the basis of force between two masses.
<h3>Acceleration of the block</h3>
a = v²/A
a = (3.9²)/0.12
a = 126.75 m/s²
Learn more about acceleration here: brainly.com/question/605631
#SPJ1
Answer:
3.73 * 10^16 photons/sec
Explanation:
power supply = 3.0 V
Emits 440 nm blue light
current in LED = 11 mA
efficiency of LED = 51%
<u>Calculate the number of photons per second the LED will emit </u>
first step : calculate the energy of the Photon
E = hc / λ
=( 6.62 * 10^-34 * 3 * 10^8 ) / 440 * 10^-9
= 0.0451 * 10^-17 J
Next :
Number of Photon =( power supply * efficiency * current ) / energy of photon
= ( 3 * 0.51 * 11 * 10^-3 ) / 0.0451 * 10^-17
= 3.73 * 10^16 photons/sec
V = f(lambda)
5/1 = lambda
lambda = 5
C. <span>C. 5 m/s away from the waves</span>