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Screenshot 2024-02-29 at 6.26.26 AM.png

Could someone please explain why the answer for the second blank is "smaller than" and not "greater than"? Doesn't the length measured by a ruler set diagonally give us a longer measurement than the actual length?
Reply 1
When you straighten the ruler it will "appear" to become longer
Original post by E K
Screenshot 2024-02-29 at 6.26.26 AM.png

Could someone please explain why the answer for the second blank is "smaller than" and not "greater than"? Doesn't the length measured by a ruler set diagonally give us a longer measurement than the actual length?


The diagram below should help and answer your confusion. :smile:
AQA_Physics_Extension_smaller_02.JPG
Reply 3
Original post by pingu41
When you straighten the ruler it will "appear" to become longer
Thank you for your explanation :smile:
Reply 4
Original post by Eimmanuel
The diagram below should help and answer your confusion. :smile:
AQA_Physics_Extension_smaller_02.JPG
It does help a lot, thank you for your help :smile:
Reply 5
Original post by Eimmanuel
The diagram below should help and answer your confusion. :smile:
AQA_Physics_Extension_smaller_02.JPG
Actually, I think I'm still confused πŸ˜‚
I do understand your diagram that the tilted ruler gives you a shorter measurement of a length,
but isn't the 'extension' an increase in the length of the spring?

If we say the actual extension of the spring measured properly on the vertical ruler was 2cm (from 8cm to 10cm on the ruler), then for the same increase in length, the extension measured on the tilted ruler would be around 2.3cm (from 6cm to 8.3cm on the ruler) and hence the extension recorded by the tilted ruler would be greater than the actual extension?
It makes more sense to me that the tilted ruler is measuring the hypotenuse of the triangle that has the same height as that on the vertical ruler 😭

Screenshot 2024-03-04 at 2.12.57 AM.png
Original post by E K
Actually, I think I'm still confused πŸ˜‚
I do understand your diagram that the tilted ruler gives you a shorter measurement of a length,
but isn't the 'extension' an increase in the length of the spring?

If we say the actual extension of the spring measured properly on the vertical ruler was 2cm (from 8cm to 10cm on the ruler), then for the same increase in length, the extension measured on the tilted ruler would be around 2.3cm (from 6cm to 8.3cm on the ruler) and hence the extension recorded by the tilted ruler would be greater than the actual extension?
It makes more sense to me that the tilted ruler is measuring the hypotenuse of the triangle that has the same height as that on the vertical ruler 😭

Screenshot 2024-03-04 at 2.12.57 AM.png


Almost forgot about it.
I suspect the reading is done as shown below to give a smaller reading.
TSR_Hooke01.JPG

A zoom-in portion of the reading.
TSR_Hooke02_zoom_in.JPG
Reply 7
Original post by Eimmanuel
Almost forgot about it.
I suspect the reading is done as shown below to give a smaller reading.
TSR_Hooke01.JPG
A zoom-in portion of the reading.
TSR_Hooke02_zoom_in.JPG
Ohh okay, never thought about it this way.
It makes much better sense now. Thank you again for your help & diagram πŸ™πŸ»πŸ™πŸ»

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