Answer: released if the laser is used 0.056 s during the surgery
Explanation:
First, you have to calculate the energy of each photon according to Einstein's theoty, given by:
Where is the wavelength, is the Planck's constant and is the speed of light
-> Planck's constant
-> Speed of light
So, replacing in the equation:
Then, the energy of each released photon by the laser is:
After, you do the inverse of the energy per phothon and as a result, you will have the number of photons in a Joule of energy:
The power of the laser is 1.1 W, or 1.1 J/s, that means that you can calculate how many photons the laser realease every second:
And by doing a simple rule of three, if are released every second, then in 0.056 s:
are released during the surgery
A substance changes from liquid to gas
Answer:
Circuit 1 and Circuit 3
Explanation:
If there is 1 Circuit and it runs out of energy, there's another one to produce the power.
John weighs 200 pounds.
In order to lift himself up to a higher place, he has to exert force of 200 lbs.
The stairs to the balcony are 20-ft high.
In order to lift himself to the balcony, John has to do
(20 ft) x (200 pounds) = 4,000 foot-pounds of work.
If he does it in 6.2 seconds, his RATE of doing work is
(4,000 foot-pounds) / (6.2 seconds) = 645.2 foot-pounds per second.
The rate of doing work is called "power".
(If we were working in the metric system (with SI units),
the force would be in "newtons", the distance would be in "meters",
1 newton-meter of work would be 1 "joule" of work, and
1 joule of work per second would be 1 "watt".
Too bad we're not working with metric units.)
So back to our problem.
John has to do 4,000 foot-pounds of work to lift himself up to the balcony,
and he's able to do it at the rate of 645.2 foot-pounds per second.
Well, 550 foot-pounds per second is called 1 "horsepower".
So as John runs up the steps to the balcony, he's doing the work
at the rate of
(645.2 foot-pounds/second) / (550 ft-lbs/sec per HP)
= 1.173 Horsepower. GO JOHN !
(I'll betcha he needs a shower after he does THAT 3 times.)
_______________________________________________
Oh my gosh ! Look at #26 ! There are the metric units I was talking about.
Do you need #26 ?
I'll give you the answers, but I won't go through the explanation,
because I'm doing all this for only 5 points.
a). 5
b). 750 Joules
c). 800 Joules
d). 93.75%
You're welcome.
And #27 is 0.667 m/s .