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A sodium lamp emits light at the power P = 100 W and at the wavelength λ = 570 nm?
A sodium lamp emits light at the power P = 100 W and at the wavelength λ = 570 nm, and the emission is uniformly in all directions. The frequency is 5.25951681*10^14 Hz, and the energy of each photon in the emission process is 3.48499271*10^-19 J. Photons are emitted from the lamp at a rate of 2.86944647*10^20 photons/second.
a) At what distance from the lamp will a totally absorbing screen absorb photons at the rate of 1.00 photon/(cm^2*s)?
b)What is the rate per square meter at which photons are intercepted by a screen at a distance of 3.00 m from the lamp?
Physics11 months ago"I once got caught tp-ing an old folks home, and they made me host majong night." Where is this quote from? If from tv show, include episode?
My friend suspects that it might be from the character Steve Palchuk from the Tales of Arcadia cartoons, but they aren't sure, and also can't remember which episode he would have said it in.
1 AnswerComics & Animation1 year agoMagnetic field from two semicircular arcs?
Two semicircular arcs have radii R2 = 3.37 cm and R1 = 2.10 cm, carry current i = 0.855 A, and have the same center of curvature C. What is the magnitude of the magnetic field?
I used the equation B=(μ0*i)/2πr, and B=B1-B2
B1 = (μ0*i)/2πR1 = 8.14285714×10^(−6)
B2 = (μ0*i)/2πR2 = 5.07418398×10^(−6)
B = 3.06867317×10^(−6)
My homework website is saying that this answer is incorrect, so could someone please tell me what I'm doing wrong?
Physics1 year agoSuppose that in a lightning flash the potential difference between a cloud and the ground is 1.0×109 V?
Suppose that in a lightning flash the potential difference between a cloud and the ground is 1.0×109 V and the quantity of charge transferred is 32 C.
(a) What is the change in energy of that transferred charge?
(b) If all the energy released could be used to accelerate a 1100 kg car from rest, what would be its final speed?
2 AnswersPhysics2 years ago
The figure shows a Gaussian surface in the shape of a cube with edge length 1.40 m.?
What are (a) the net flux through the surface and (b) the net charge qenc enclosed by the surface if
the electric field in the region is in the positive y direction and has a magnitude that is given by E = 2.67y N/C? What are (c) the net flux and (d) net enclosed charge if the electric field is in the xy plane and has components Ex = -5.16 N/C and Ey = (5.04 + 2.67y) N/C?
Physics2 years agoIf the initial concentration of SO2Cl2 is 1.00 M, how long will it take for the concentration to decrease to 0.72 M?
The decomposition of SO2Cl2 is first order in SO2Cl2 and has a rate constant of 1.36×10^(-4) s−1 at a certain temperature.
1 AnswerChemistry2 years agoHow to solve Newton s Law of Cooling when not given initial temperature?
T(10) = 415 F
T(20) = 347 F
Surrounding Temperature = 75 F
I have the equation T(t) = 75 + ce^(-kt) and am unsure of how to find the values for c and k due to not knowing the initial temperature
2 AnswersMathematics2 years agoLinear Algebra y''+y=0 is y(x)=c1(cosx)+5c2(cosx)?
I have a true-or-false question, and I need to find if the general solution to y''+y=0 is y(x)=c1(cosx)+5c2(cosx)
Apparently the answer is supposed to be false, but I don't understand why and have attempted to solve the problem multiple times.
2 AnswersMathematics2 years ago
Find the potential difference (delta V) between points C and D?
S1 and S2 are closed switches. There are two resistors, with R1 = 10 ohms and R2 being unknown. The current through R1 is 1.2 F, and the emf gives 12 V.
3 AnswersPhysics2 years agoThe uniform current density J flows through a surface that is a spherical cap of radius R. What is the total current through this surface?
The cap is centered on the z+ axis and has angular width of 60 degrees as measured form the z+ axis.
1 AnswerPhysics2 years agoUse polar coordinates to find the volume of the given solid.?
z = sqrt(x^2 + y^2)
x^2 +y^2 = 81
1 AnswerMathematics2 years ago
2nd semester college physics: "Two identical particles, each with charge 1.25 nC..."?
Two identical particles, each with charge a charge of 1.25 nC, are fixed in the first and fourth quadrants, respectively, of a cartesian coordinate system. Each particle is 0.25 m from the origin along a line that makes an angle of 45 degrees from the axis. (This system can be seen in the figure below.)
A third charge, q', is placed along the y-axis between the other two charges. If the net electric field at the origin is 0, then what is the magnitude of q'?
1 AnswerPhysics2 years agoWhen finding the inverse of a square root function, does one square the function or divide out the coefficient first?
In context of 2\sqrt{x+2}-3
Homework Help5 years agoIf you're 5'7" (170 centimeters), how tall is someone for whom the top of his/her head reaches your shoulders?
For a fanfic; one of the characters is 5'7" and the other comes up to his shoulders. Height is a plot point.
1 AnswerBooks & Authors6 years agoMagical girl fans: what would you like to see in a magical girl series?
I'm currently plotting one, and I would like some random ideas that I can throw against the walls of my brain.
2 AnswersComics & Animation6 years agoWhat are some ways for a guy to propose to a girl?
I'm starting to write a fanfic in which one character tries to propose to his girlfriend several times, but each time he doesn't actually ask her due to them being called for duty or something. What are some ways for him to propose?
Nothing over the top please.
2 AnswersSingles & Dating6 years ago
