July 16, 2019, 08:36:06 pm

### AuthorTopic: Could someone please explain this question  (Read 85 times) Tweet Share

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#### jando

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##### Could someone please explain this question
« on: July 11, 2019, 01:02:08 pm »
0
Hey,

I was wondering if someone could explain this question to me.

Cheers.

#### DrDusk

• MOTM: MAY 19
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• sin(x) = tan(x) = x
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##### Re: Could someone please explain this question
« Reply #1 on: July 11, 2019, 05:04:35 pm »
+1
Hey,

I was wondering if someone could explain this question to me.

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
« Last Edit: July 11, 2019, 05:20:22 pm by DrDusk »
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#### r1ckworthy

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##### Re: Could someone please explain this question
« Reply #2 on: July 11, 2019, 05:12:52 pm »
+1
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  . Great explanation!
HSC 2019: English Advanced || Mathematics || Mathematics Extension 1 || Physics || Chemistry || Science Extension || Ancient History ||

The Yr12 journey- a diary I "hope" to update... || Send some questions to boost my ego :)

#### DrDusk

• MOTM: MAY 19
• Forum Regular
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• sin(x) = tan(x) = x
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##### Re: Could someone please explain this question
« Reply #3 on: July 11, 2019, 05:19:16 pm »
0
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  . Great explanation!

Oh god, today I realized how stupid I am lol. I can't even properly convert units
UNSW 2019-2023:

HSC 2018:
Atar aim:  95+ (Achieved)

Very soon to be HSC/Prelim Physics Tutor!

sin(x) = tan(x) = x, for all x

#### r1ckworthy

• MOTM: APR 19
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##### Re: Could someone please explain this question
« Reply #4 on: July 11, 2019, 05:25:46 pm »
0
Oh god, today I realized how stupid I am lol. I can't even properly convert units

Hey, it happens to the best of us
HSC 2019: English Advanced || Mathematics || Mathematics Extension 1 || Physics || Chemistry || Science Extension || Ancient History ||

The Yr12 journey- a diary I "hope" to update... || Send some questions to boost my ego :)