Answer:
the number of photons of yellow light does the lamp generate in 1.0 s is 7 x 
Explanation:
given information:
power, P = 25 W
wavelength. λ - 580 nm = 5.80 x
m
time, t = 1 s
to calculate the number of photon(N), we use the following equation
N = λPt/hc
where
λ = wavelength (m)
P = power (W)
t = time interval (s)
h = Planck's constant (6.23 x
Js)
c = light's velocity (3 x
)
So,
N = λPt/hc
= (5.80 x
)(25)(1)/(6.23 x
)(3 x
)
= 7 x 
She does 200J .
We know she uses 20N of force and 10m is the distance. We multiply both numbers and we are given our answer of 200J. Hope this was helpful. :)
(6) first choice: the frequency appears higher and wavelength is shorter.
The car approaches a stationary observer and so the sound will appear to have shorter wavelength. This creates an effect of its siren to sound with higher frequency than it would do if both were stationary.
(7) The Doppler formula for frequency in the case of a stationary observer and source approaching it is as follows:

The wavelength is then

The third choice "0.80m; 431Hz" is correct
Answer:
The frequency , speed and wavelength of an electromagnetic wave are related by the formula
Speed = frequency x wavelength
frequency = speed / wavelength
substituting the values
frequency = 3 x #10 ^8# m /s / 1 x #10^15# m
= 3 x #10^-7# /s
In this exercise we have to know the definition of energy to understand what is transferred to a body, like this:
Work
<h2>What is energy?</h2>
Despite being used in many different contexts, the scientific use of the word energy has a well-defined and precise meaning: Innate potential to perform work or perform an action. Anything that is working, moving another object, or heating it up, for example, is expending (transferring) energy.
With this definition we can say that the only alternative that responds to this is work.
See more about energy at brainly.com/question/1932868