Answer:
3.066×10^21 photons/(s.m^2)
Explanation:
The power per area is:
Power/A = (# of photons /t /A)×(energy / photon)
E/photons = h×c/(λ)
photons /t /A = (Power/A)×λ /(h×c)
photons /t /A = (P/A)×λ/(hc)
photons /t /A = (680)×(678×10^-9)/(6.63×10^-34)×(3×10^-8)
= 3.066×10^21
Therefore, the number of photons per second per square meter 3.066×10^21 photons/(s.m^2).
The longitude based on the time difference is 15 degrees.
<h3>Longitude of complete rotation of the Earth</h3>
The longitude of a complete rotation of the earth in a 24 hours is calculated as follows;

<h3>Time difference</h3>
The time difference between the local apparent solar time and the Greenwich time is calculated as follows;

Since it is one hour time difference, the longitude is 15 degrees.
Learn more about Earth longitude here: brainly.com/question/1939015
WORKDONE = FORCE * DISPLACEMENT
W=F*S
HERE, THE FORCE = 100N AND DISTANCE = 20M
WORKDONE = 100*20
WORKDONE=2000
ITS S.I UNIT IS JOULE OR J
SO, 2000J
The ball may attracted to the magnet.
<h3>How can we understand that the hanging ball will be attracted to the magnet or not?</h3>
- From the question, we understand that the ball is attracted by the north pole of the bar magnet, then the bar magnet flipped over and the south pole is brought near the hanging ball.
- As we know, in this type of experiments of bar magnet most of the times the ball is made out of steel.
- Steel is a magnetic material.
- Magnetic materials gets attracted to the magnet at both the North and South pole.
- This can be compared to how neutral objects also gets attracted to the positively and negatively charged rods through the Polarization force.
So, If the bar magnet is flipped over and the south pole is brought near the hanging ball, The ball will be attracted to the magnet.
Learn more about the bar magnet:
brainly.com/question/27943723
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