ATAR Notes: Forum

HSC Stuff => HSC Science Stuff => HSC Subjects + Help => HSC Physics => Topic started by: jando on July 11, 2019, 01:02:08 pm

Title: Could someone please explain this question
Post by: jando on July 11, 2019, 01:02:08 pm: Hey,

I was wondering if someone could explain this question to me.
The answer is B.

Cheers.
Title: Re: Could someone please explain this question
Post by: DrDusk on July 11, 2019, 05:04:35 pm: Quote from: jando on July 11, 2019, 01:02:08 pm
Hey,

I was wondering if someone could explain this question to me.
The answer is B.

Cheers.
Recall the formula:
$F = mrw^2, w = 4\pi$
$F = 0.015\times 0.8\times16\pi^2$

Thanks to r1ckworthy for pointing out my mistake in converting Grams to Kg hahaaha
Title: Re: Could someone please explain this question
Post by: r1ckworthy on July 11, 2019, 05:12:52 pm: Quote from: DrDusk on July 11, 2019, 05:04:35 pm
It appears they've made a mistake.
Recall the formula:
$F = mrw^2, w = 4\pi$
In their calculations I think they've forgotten the Pi which gives you the answer of 1.9. The actual answer would be:
$F = 0.15\times 0.8\times16\pi^2$

Hey DrDusk,
Your conversion for 'm' is wrong, it should be 0.015 kg instead of 0.15 kg, which when I calculated it checks out to B ;D. Great explanation!
Title: Re: Could someone please explain this question
Post by: DrDusk on July 11, 2019, 05:19:16 pm: Quote from: r1ckworthy on July 11, 2019, 05:12:52 pm
Hey DrDusk,
Your conversion for 'm' is wrong, it should be 0.015 kg instead of 0.15 kg, which when I calculated it checks out to B ;D. Great explanation!

Oh god, today I realized how stupid I am lol. I can't even properly convert units ;D
Title: Re: Could someone please explain this question
Post by: r1ckworthy on July 11, 2019, 05:25:46 pm: Quote from: DrDusk on July 11, 2019, 05:19:16 pm
Oh god, today I realized how stupid I am lol. I can't even properly convert units ;D

Hey, it happens to the best of us ;D