How Do You Calculate the Final Speed of a Comet in Orbit?

AI Thread Summary
To calculate the final speed of a comet in orbit, one must apply the principle of conservation of angular momentum. The angular momentum at the closest approach (r1) can be expressed in terms of the initial speed (v1) and the distance from the Sun. At a later distance (r2), the angular momentum must equal that at r1, allowing for the determination of the final speed (v2) using the angle θ between the position and velocity vectors. The initial attempt using mv1cos(90-theta) was incorrect, indicating a need for a different approach. Ultimately, setting the angular momentum equations equal will yield the correct final speed of the comet.
Qnslaught
Messages
8
Reaction score
0

Homework Statement



(a) A certain comet of mass m at its closest approach to the Sun is observed to be at a distance r1 from the center of the Sun, moving with speed v1. At a later time the comet is observed to be at a distance r2 from the center of the Sun, and the angle between rvec2 and the velocity vector is measured to be θ. What is v2?


Homework Equations





The Attempt at a Solution



I thought it would be mv1cos(90-theta). But it's counting that wrong, and I only have one more attempt at this problem, and I'm not sure how to approach it.
 
Physics news on Phys.org
Angular momentum is conserved, so find expressions for the angular momentum at the two points and set them equal.
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanged 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...

Similar threads

Replies
1
Views
2K
Replies
2
Views
2K
Replies
5
Views
3K
Replies
6
Views
8K
Replies
6
Views
195
Replies
4
Views
7K
Back
Top