Solving Density Problems: Neutron Stars Homework

  • Thread starter Thread starter drewsteriam
  • Start date Start date
  • Tags Tags
    Density
AI Thread Summary
Neutron stars are incredibly dense, with a typical mass of 2.7 x 10^28 kg and a radius of 1.2 x 10^3 m. To find the density, the formula density = mass/volume is applied, leading to a calculation of the star's density. Additionally, if a dime were made from neutron star material, its volume of 2.0 x 10^-7 m³ would result in a weight of approximately 2.2 pounds. The discussion highlights the need for clarity on relevant equations and problem-solving approaches in physics. Overall, the density of neutron stars and the weight of a dime made from their material are key focus points.
drewsteriam
Messages
3
Reaction score
0

Homework Statement


Alright, this chapter in my AP Physics class has been giving me all sorts of problems, so need tons of help. Here is the first problem:
Neutron stars consist only of neutrons and have unvelievably high densities. A typical mass and radius for a neutron star might be 2.7 x 10^28 kg and 1.2 x 10^3 m. (a) Find the density of such a star. (b) If a dime (V=2.0 x 10^-7 meters cubed) were made from this material, how much would it weigh (in pounds)?


Homework Equations


I'm not sure what equations are relevant, but I will give it a try: P+.5p(v)^2+pgy=p+.5pgy


The Attempt at a Solution


I don't really know any of this so I don't know where to start. Any help would be appreciated, Thanks.
 
Physics news on Phys.org
Density = mass/volume

2.2 pounds = 1 kg
 
Thanks, that was a lot simpler than I thought it would be.
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top