Dimensions of TV

[Guest]

I own a 32" flat screen television. Is there a way to determine the length and width from the diagonal ? I realize I could physically measure for dimensions, but I wanted to calculate mathematically.

[Guest]

There is no way to determine the width and height just from the diagonal length. You need more information such as the aspect ratio of the tv (4:5 or 16:9, etc)

Hope this helped,

R. Baber.

[Guest]

Thanks, that helped.

[Guest]

If your TV is 4:5 and it were actually 4 high by 5 wide then the diagonal would be 6.4 which is 1/5 of your 32 inch diagonal TV.
So the height of your 32 inch diagonal TV is 5 x 4 = 20 inches by 5 x 5 = 25 inches

[Guest]

I don't understand how you obtained the 6.4.

[Guest]

I took it from the earlier post....aspect ratio 4:5.......????? I think the standard aspect ratio is 4:3

But for the 4 :5 ....that is the ratio of the short side to the long side of the rectangle
By pathagoras Sqroot of ( 4^2 + 5^2) = Sqrt of 41 = 6.4 which is 1/5 of your diagonal so your sides will by 5 times.

But for 4:3 ratio the diagonal is 5 by pathagoras which is 1/6.4 of your diagonal of 32
so your sides will be 4 x 6.4 = 25.6 and 3 x 6.4 = 19.2

[Guest]

I am not totally clear .

[Guest]

aspect ratio is ratio of width to height of the screen
4:3...... is 4 units wide by 3 units high and as this is a right angle rectangle the diagonal then is 5 units...by Pythagoras.

If the screen was a 50 inch screen with 4:3 aspect ratio....then the diagonal would be 50 inches as stated, its width would be 40 inches and its height would be 30 inches.

4:3 was used more for older TVs.....newer TVs are probably 16:9

[Guest]

" aspect ratio is ratio of width to height of the screen " I understand this.
" 4:3...... is 4 units wide by 3 units high and as this is a right angle rectangle the diagonal then is 5 units...by Pythagoras. " I don't understand the 5 units.

[Guest]

4:3 is the ratio of width to height......you understand that......

Then you must understand the any rectangle that has the similar shape...... width : height of 4 : 3 is a similar shape

similar shapes may be different sizes, eg half as big or twice as big or any factor of the other.

so if we consider a 4 unit by 3 unit rectangle
then by Pythagoras......

4 x 4 = 16
3 x 3 =9
9 + 16 = 25
Sqroot of 25 = 5

So 5 units is the length of the diagonal of the 4 x 3 rectangle

your diagonal is 32 inches
that is 6.4 times 5
so your rectangle is 6.4 times the size of the similar rectangle 4 x 3
so your width is 6.4 x 4 = 25.6 inches
and your height is 6.4 x 3 = 19.2 inches

if your aspect ratio is 4 : 3.....above calcs is OK ..... but newer TVs are.... probably 16 : 9

[Guest]

I understand now. Thanks.

[Guest]

So if your TV is a 32 inch 16:9
Then for a W x H of 16 x 9 the diagonal is 18.36
That is 1.743 times smaller
so width of your TV is 16 x 1.743 = 27.89 inches
and height is 9 x 1.743 = 15.69 inches

[Guest]

Thanks for additional info.

One question: Would the calculations be the same for a laptop computer and tablet screen ? I don't know the aspect ratio for either.

[Guest]

Yes, computer screens are usually measured by length of diagonal.

If you have a laptop you must have access to Google, why not "google" some of these questions.

[Guest]

Ok, I will. Thanks again.

[leesajohnson]

You can find the actual measurement of TV screen by measuring the diagonal of the screen.