surface area,colume of cylinder, cone & hemisphere

[mathismaths]

so i have 2 questions to ask:
Q1:


So i find volume of hemisphere:2/3*π*r^3
volume of cylinder is π*r^2*h
volume of cone is 1/3*π*r^2*h

now how to proceed to solve, calculate h,and use the ratio?

Q2


here i know the formulas as stated in Q1(above) but how to proceed to solve?


help would be appreciated

 

[mathismaths]

i would appreciate how to do it urgently have to submit for my son's exam evaluation, please and thanks in advance.Also its volume not colume in the title, sorry for mistake.

 

[HallsofIvy]

What? This is to be submitted for your son's exam evaluation? Is this exam evaluating his ability in math or your ability to get other people to do his work? That's outrageous! What do you have against your son?

 

[mathismaths]

What? This is to be submitted for your son's exam evaluation? Is this exam evaluating his ability in math or your ability to get other people to do his work? That's outrageous! What do you have against your son?

sorry not exam evaluation but summerwork and i tutor him myself and i dont spoonfeed him but need to understand every question beforehand so i can help him if he has doubts in them and these were the questions i'm unable to do.He have medical issues which led to him joining school late so he has difficulty to cope and i have to help him guide.i hope u can understand.

If what im doing is wrong then the admins can delete this post and i can apologise but there is no wrongdoing here.

 

[Deleted member 4993]

so i have 2 questions to ask:
Q1:
View attachment 19166

So i find volume of hemisphere:2/3*π*r^3
volume of cylinder is π*r^2*h
volume of cone is 1/3*π*r^2*h

now how to proceed to solve, calculate h,and use the ratio?

Q2
View attachment 19167

here i know the formulas as stated in Q1(above) but how to proceed to solve?


help would be appreciated

First let height of the cylinder = H_l and height of the cone H_n

Then get the expression for the total volume of the structure by adding individual volumes.

Then use the ratio of the volumes (3 equations) to calculate the other unknowns.

If you are still stuck, please let us know.

 

[mathismaths]

View attachment 19178

First let height of the cylinder = H_l and height of the cone H_n

Then get the expression for the total volume of the structure by adding individual volumes.

Then use the ratio of the volumes (3 equations) to calculate the other unknowns.

If you are still stuck, please let us know.

so this is what is have done until now
Hemisphere volume V1 = 128?/3

they say

V1:V2:V3 = 6:27:4

V1: (V1 + V2 + V3) = 6: (6 + 27 + 4)

VP = V1 + V2 + V3

(128?/3) : VP = 6 : 37

VP = 2368?/9

View attachment 19178

First let height of the cylinder = H_l and height of the cone H_n

Then get the expression for the total volume of the structure by adding individual volumes.

Then use the ratio of the volumes (3 equations) to calculate the other unknowns.

If you are still stuck, please let us know.

thanks i understood first question and the second one?

 

[Deleted member 4993]

so this is what is have done until now
Hemisphere volume V1 = 128?/3

they say

V1:V2:V3 = 6:27:4

V1: (V1 + V2 + V3) = 6: (6 + 27 + 4)

VP = V1 + V2 + V3

(128?/3) : VP = 6 : 37

VP = 2368?/9

thanks i understood first question and the second one?

You understand what you need to FIND (calculate).

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

https://www.freemathhelp.com/forum/threads/read-before-posting.109846/#post-486520

Please share your work/thoughts about this assignment.

 

[mathismaths]

You understand what you need to FIND (calculate).

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

https://www.freemathhelp.com/forum/threads/read-before-posting.109846/#post-486520

Please share your work/thoughts about this assignment.

for second question i have done first part :
volume of iron = volume of small cone = 0.524
volume of lead = volume of cylinder - volume of small cone = 37.2

how to do second part of second question?

 

[Deleted member 4993]

for second question i have done first part :
volume of iron = volume of small cone = 0.524
volume of lead = volume of cylinder - volume of small cone = 37.2

how to do second part of second question?

Do you know the following equation from sciences (Physics):

If an object is made of a uniform material with density d, and if the volume of the object is V, then mass M of the object is:

M = d * V