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Unregistered
02-25-2008, 11:09 AM
Widescreen (16:9) and 4:3 TVs will have a different formula. The manufacturers cheat and tell you the diagonal length, to make the number look bigger, but how do you figure out the width/height with the diagonal length?

That should get added to the list of conversions.

JohnS
02-25-2008, 07:10 PM
Widescreen (16:9) and 4:3 TVs will have a different formula. The manufacturers cheat and tell you the diagonal length, to make the number look bigger, but how do you figure out the width/height with the diagonal length?

That should get added to the list of conversions.

For a 4:3 tv, the height:width:diagonal are in the ratio 3:4:5. So the height is 3/5 x the diagonal, and width 4/5
(or 60% and 80%).

For a 16:9 tv, the ratio is 9:16:sqrt(337). Height is 9*diag/sqrt(337), width is 16*diag/sqrt(337), or about 49% and 87% of diagonal.

Unregistered
06-01-2009, 12:06 AM
nice work thanks

Unregistered
11-23-2009, 09:53 PM
diagonal is 25, height is 15, width?

JohnS
11-24-2009, 08:08 AM
diagonal is 25, height is 15, width?

20" as explained in post 2.

Unregistered
06-21-2010, 07:44 AM
nice job, finally i got it, but honestly the 16:9 not so much, i guess i can find the % given but i want to know how u derive at the % , if u don't mind
tks

JohnS
06-21-2010, 08:42 AM
The diagonal squared is equal to the sum of the sides squared. From the 16:9 ratio, I computed the diagonal, and refigured each side to the diagonal as a ratio. If the sides are 9 and 16, the diagonal is sqrt(337) = 18.3576

Unregistered
07-08-2010, 05:15 PM
This is pythagorean theorem: The sum of the sides squared is equal to the diagonal squared

Unregistered
09-07-2010, 12:10 AM
You take both sides 3 and 4 and use arctan to get the angles that are not 90deg. Repeat the process with the 16 and 9. Then use the law of sines to get that the W*0.85=SD. Where W is the widescreen diagonal and SD is the 3:4 diagonal measurement.

Ez breezy
10-06-2010, 11:32 AM
My teacher gave me a worksheet that says ''Going to the mtric lengths''.And im on number 2 it says what is the height of the tv.i have no idea and it doesnt tell us what kind of tv it is.im really confused on it.who can help me on this!!!!!

Robert Fogt
10-06-2010, 02:04 PM
My teacher gave me a worksheet that says ''Going to the mtric lengths''.And im on number 2 it says what is the height of the tv.i have no idea and it doesnt tell us what kind of tv it is.im really confused on it.who can help me on this!!!!!
You'll need to give us more information. Type out the complete question.

Unregistered
10-28-2010, 12:42 PM
A television screen measures approx. 18.5 in. high and just over 26 in. wide.
How should the size of this television be advertised?

My question is how do I figure this problem out? I have tried to add or divide but it does not make sense to me! Please help :)

JohnS
10-28-2010, 01:21 PM
A television screen measures approx. 18.5 in. high and just over 26 in. wide.
How should the size of this television be advertised?

My question is how do I figure this problem out? I have tried to add or divide but it does not make sense to me! Please help :)

Hint, hint: A guy named Pythagoras has a theorem about this very subject, even though TVs didn't exist in his time, only triangles.

Unregistered
11-25-2010, 09:17 AM
Let d = diagonal, l = length, w = width. Let AR = l/w. AR = 16/9 = 1.78 for a wide screen.
We are given d. We want to compute l and w. Below ** means exponential, * means times, and SQRT means square root.

Solution:
l = AR * w
d**2 = l**2 + w**2 (Pythagorus). Substituting

d**2 = (AR**2) * (w**2) + w**2 = (AR**2 + 1) * w**2. So,
w**2 = d**2/(AR**2 + 1). So the general formula is

w = = d/(SQRT(AR**2 + 1)
l = AR * w.

For the wide screen AR = 1.78. So
w =.49 * d
l =.87 * d

For standard screen, do the math for the appropriate AR.

Unregistered
12-20-2010, 05:10 AM
How i can measure horizontal width linearity % in a color television by using chroma pattern generator?

shel
04-12-2012, 12:07 PM
Since the width: height: ratio of the screen is 4:3 what number would represent the diagonal of the screen? Write a ratio of height: width: diagonal. help i have no idea how to answer That should get added to the list of conversions.[/QUOTE]

Mrs X
04-13-2012, 01:11 AM
Since the width: height: ratio of the screen is 4:3 what number would represent the diagonal of the screen? Write a ratio of height: width: diagonal. help i have no idea how to answer That should get added to the list of conversions.

Remember Pythagoras' Theorem? - (3,4,5 triangle?)

If you have a right angle triangle, the square of the hypotenuse will be the sum of the squares of the other sides.

3² = 9

4² = 16

3²+4² = 9 + 16 = 25. The square root of 25 is ??

Unregistered
01-05-2013, 11:29 AM
I have a projected screen that is approx. 14' x 7' high. I can figure out the feet to inches
But how do I calculate the diagonal size? So I can say I have a 000" screen? 14' (168") x
7' (84").

JohnS
01-05-2013, 04:33 PM
I have a projected screen that is approx. 14' x 7' high. I can figure out the feet to inches
But how do I calculate the diagonal size? So I can say I have a 000" screen? 14' (168") x
7' (84").

See posts 7,8, 14

sqrt(84*84 + 168*168) = 187.8" diagonal

Clark
01-29-2013, 10:54 AM
A television screen measures approx. 18.5 in. high and just over 26 in. wide.
How should the size of this television be advertised?

My question is how do I figure this problem out? I have tried to add or divide but it does not make sense to me! Please help :)

If you are a DVD Manufacturer, you would advertise this TV with the misnomer "Fullscreen".
If you were a TV Manufacturer you would be a little more accurate and call it "4:3" or "Standard Definition".
If you were an honest salesman, you would advertise the TV as "obsolete".

If you live in the U.S., tell your teacher that her test needs to be updated to comply with current FCC digital transmission regulations and see how fast you get an "F" for "Forward Thinking".

In the unlikely event you actually get BONUS points for this answer, you can count yourself blessed to have a rare teacher who recognizes discovery and learning in any form it may manifest in you.