Question

http://maxpapers.com/wp-content/uploads/2012/11/9709_s13_qp_52.pdf
q6

Answer 1

Should we take the moment about V?

Answer 2

how much time do you have for this problem?

Answer 3

10 minutes.

Answer 4

yeah 10 minutes is not enough for a question i guess we have to use y'=m(cone)*d0+m(particle)*d1/m(particle)+m(cone)

Answer 5

Lol, good night and thanks for your time :)

Answer 6

@IrishBoy123

Answer 7

which bit

if part i, ie for the CoM, are you taught formula, or do you want to integrate?

volume of rev of the cone ...

Answer 8

nope just the formula

Answer 9

what reference point should we use the vertex point V as the origin or at the bottom in the axis of symmetry

Answer 10

what is the formula for a cone, where is its CoM. not something i carry around

for the particle, you just need to resolve it along the axis

Answer 11

do it about any point you like but you need a formula for that point.

Answer 12

The position of the center of mass of a solid cone is 3/4*height from the vertex.

Answer 13

or 1/4 from the base...same thing.

but go from the vertex.

P is 0.4 cos 60 from vertex

Answer 14

shouldnt we use 1/4 fro the base if we use the base as the origin.

Answer 15

either way works, you can work from the top and then adjust.

i'd go from the top because we resolve the 0.4 particle thingy from the vertex, but you decide.

once we know the distance from the vertex, we use the 0.6 height to make it the distance from the base.

Answer 16

or use the base as the origin. either way is good

Answer 17

0.6 * (3/4) * 0.5 + 0.4 *(1/2) * 0.2 = 0.8 * x

from the vertex

Answer 18

do you agree? or do we need to draw something?

Answer 19

typo, should be

0.7* x

Answer 20

for the CoM, we are calculating moments about the axis shown, as if the whole thing ws spinning into the page