- #1
indiansfan4life
- 16
- 0
Since no one seems to be helping me, maybe you will help me when I post my exact work that I did. I just need someone to check them all and make sure I did the right equations and if I got the right answers or not. This is for a grade, and I desperately need a passing grade on this worksheet to even pass the class. I made an honest attempt at each.
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?
Given:
f=100.4 MHz
3x10^8
f=100.4x10^6
1004000000
-----------
3x10^8
=.335 m
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?
Given:
v=2.45x10^8 m/s
3x10^8
n=c/v
2.45 x 10^8
------------
3 x 10^8
=1.22
17. What is the intensity of a light that has a lumnious flux of 750 lumens?
Given:
P= 750 lm
E= ?
E=P/4(pie)
E=750 lm/4(pie)
E=589.05 cd
18. What is the illuminance provided by a light with a luminous flux of 1120 lm when it is 2.3 meters away?
Given:
E= ?
P= 1120 lm
d= 2m
E=P/4(pie)d^2
E=1120 lm/4(pie)2^2
E=22.28 lx
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.
Given:
airn=1
n=?
90 degrees
n1sinQ1=n2sinQ2
sin(9)=n2sin(nr)
2.417xsinQ2=1sin90
=24.44 degrees
20. What is the critical angle of light going from quartz to air?
Given:
nquartz=1.544
sin x= 1/1.544 = .647
sin-1(.647)
=40.37 degrees
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?
d= 4.6 m
cd= 78
P= 980.2
E=P/4(pie)d2
cd=P/4(pie)
CD4(pie)=P
78(4)(pie)
E=980.2/4(pie)(4.6)^2
E=3.69 lx
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?
Given:
f=100.4 MHz
3x10^8
f=100.4x10^6
1004000000
-----------
3x10^8
=.335 m
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?
Given:
v=2.45x10^8 m/s
3x10^8
n=c/v
2.45 x 10^8
------------
3 x 10^8
=1.22
17. What is the intensity of a light that has a lumnious flux of 750 lumens?
Given:
P= 750 lm
E= ?
E=P/4(pie)
E=750 lm/4(pie)
E=589.05 cd
18. What is the illuminance provided by a light with a luminous flux of 1120 lm when it is 2.3 meters away?
Given:
E= ?
P= 1120 lm
d= 2m
E=P/4(pie)d^2
E=1120 lm/4(pie)2^2
E=22.28 lx
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.
Given:
airn=1
n=?
90 degrees
n1sinQ1=n2sinQ2
sin(9)=n2sin(nr)
2.417xsinQ2=1sin90
=24.44 degrees
20. What is the critical angle of light going from quartz to air?
Given:
nquartz=1.544
sin x= 1/1.544 = .647
sin-1(.647)
=40.37 degrees
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?
d= 4.6 m
cd= 78
P= 980.2
E=P/4(pie)d2
cd=P/4(pie)
CD4(pie)=P
78(4)(pie)
E=980.2/4(pie)(4.6)^2
E=3.69 lx