Density word problem A 300 kg meterorite is in circular motion orbiting a far

AI Thread Summary
The discussion revolves around solving a density word problem involving a 300 kg meteorite in circular motion. The formula provided, GMplanet = (v^2 x d)/a, is questioned for clarity, particularly regarding the variables "d" and "a." Participants suggest that "d" represents distance or radius, while "a" remains undefined and causes confusion. The correct formula for orbital velocity, v^2 = GM/r, is highlighted as the appropriate approach to solve the problem. Ultimately, the focus is on correctly identifying and assigning variables to solve for acceleration and density.
vipson231
Messages
23
Reaction score
0

Homework Statement



So my professor gave me this formula GMplanet = (v^2 x d)/a to solve for the question and told me that m/v = density. I was told then to multiply the end result of m by 1000 and v by 1,000,000 to get the answer. I am given all the knowns except the acceleration. How do i find the acceleration?
 

Attachments

  • a 300 kg...jpg
    a 300 kg...jpg
    9.2 KB · Views: 514
Physics news on Phys.org


Start by identifying your variables and assign any given values. It looks like you're using "v" for both velocity and volume. What's d? What's a?
 


I was told that the distance is equal to the radius which is equal to 2.00 x 10^8 and that the velocity is 7000 m/s for the faraway planet.

Once I plug these values into the formula it looks like

(6.67 x 10^-11)(Mass of planet)= (7000)^2 x (2.00 x 10^8) / a

However what do i do with the a? so confused :(
 


vipson231 said:
I was told that the distance is equal to the radius which is equal to 2.00 x 10^8 and that the velocity is 7000 m/s for the faraway planet.

Once I plug these values into the formula it looks like

(6.67 x 10^-11)(Mass of planet)= (7000)^2 x (2.00 x 10^8) / a

However what do i do with the a? so confused :(

You need to get the quantities and what they represent sorted out. Read the problem statement and assign variable names to the numbers given. For example, the meteorite is given a mass of 300 kg, so define m1 = 300 kg. Do the same for the other numbers given in the problem statement, assigning each an appropriate variable.

It's not clear to me what the formula you've written out is supposed to represent. Perhaps it's a misinterpretation of the formula for the orbital velocity for a body in circular orbit at orbit radius r around a planet of mass M? That would be:

$$v^2 = \frac{GM}{r}$$

I don't know what your "d" or "a" are supposed to represent in this scenario.
 


The formula that you provided for the orbital velocity above is indeed the right interpretation of the question. I perhaps either copied it wrong or didn't use the right formula. I'll try to solve this question using your formula. Thanks =)
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...

Similar threads

Back
Top