What Are the Correct Answers to These Physics and Optics Problems?

  • Thread starter Thread starter indiansfan4life
  • Start date Start date
AI Thread Summary
The discussion revolves around solving various physics and optics problems, including topics like wavelength, index of refraction, intensity, and illuminance. The user provides answers to several questions but expresses uncertainty about some calculations, particularly regarding intensity and illuminance. They demonstrate attempts at solving problems by showing their work, especially for questions involving wavelength and refraction angles. Key calculations include deriving a wavelength of 0.335 m and an index of refraction of 1.22. Overall, the user seeks clarification and assistance to improve their understanding of the concepts involved.
indiansfan4life
Messages
16
Reaction score
0
analysis:
10. the picture that we see in a mirror is called the
my answer=image
11. the actual object that makes a picture that we see on a mirror is called the
my answer=specular

-problems- show your work

15. What is the wavelength of a wave with a frequency of 100.4 MHz?

16. A substance allows light to travel through it with a velocity of 2.45 x10^8 m/s. What is the substances index of refraction?

17. What is the intensity of a light that has a lumnious flux of 750 lumens?

18. What is the illuminance provided by a light with a luminous flux of 1120 lm when it is 2.3 meters away?

19. What would the angle of refraction be if a light ray starts in a diamond and goes into the air it has an angle of incidence of 9 degrees.

20. What is the critical angle of light going from quartz to air?

22. What is the illuminance of a light when it is 4.6 m away from a light with an intensity of 78 candle power?

thanks for any help I don't know what I am doing

Here's my answers:

#15: .335 m
#16: 1.22
#17: I was not sure how to do this one.
#18: I was also not sure how to do this one.
#19: 24.44 degrees
#20: 40.37 degrees
#22. 3.6
 
Physics news on Phys.org
Show that you've tried. Providing the answers is not enough.
 
#15: 100.4 x 10^6

3 x 10^8

divide c by f

=.335

#16: 2.45 x 10^8/ 3x 10^8 =1.22
#17: Like I said, I don't know what to do
#18: Dunno what to do
#19: 2.417(SIN)Q2=1(SIN)90
=24.44 degrees
#20: I just plugged it in and got 40.37 degrees for this one
SIN X= 1/1.544 then I did some other work to get the angle

#22: I wasn't really sure with this one but I used the illuminance equation to solve. I doubt it's right.
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top