#Volume of cylinder,hemisphere and involves trignometry

1 messages · Page 1 of 1 (latest)

tidal mist
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Could somebody please help me solve this question step by step SIMPLIFIED because otherwise i might not understand where one value came from.Thanks.

cedar mica
tidal mist
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Could u explain it in more detail please

cedar mica
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I haven't learnt volume of cylinder wtv

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What's the equation for it?

cerulean current
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πr²h

cedar mica
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V = πr²h

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22.1 = π(1.5)²h

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22.1 = 2.25π x h
22.1/2.25π = h
h = 3.12651043763

Length opposite the angle is 3.12651043763. Use sin(71) = 3.12651043763/h and rearrange to get h.
sin(71) x h = 3.12651043763, so h = 3.12651043763/sin(71). Insert that into your calculator and you'll find the length of the rod.

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@tidal mist ^

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It's correct if v = πr²h is the correct formula

cedar mica
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@prime compass ^

prime compass
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You need to remember to add on the volume of the hemisphere

cedar mica
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is there a formula for it?

prime compass
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Uhh there is but I don’t remember it

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I have a feeling it’s just half the volume of a sphere

cedar mica
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oh ok ty

prime compass
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$\frac{2\pi r^3}{3}$

placid flickerBOT
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clarence

cedar mica
tidal mist
cedar mica
tidal mist
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Will do thanks

cedar mica
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np

tidal mist
# cedar mica np

I add the volume of the hemisphere to the cylinder and then do the trigonometry right?

cedar mica
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yes

tidal mist
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I got 10.78254216

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It says it isn’t the correct answer

tidal mist
cedar mica
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vol of hemisphere is half volume of a sphere

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work out the volume of a sphere using its equation

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/2

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and add it onto the vol of the cyclinder

cedar mica
tidal mist
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I did