Recent content by mjolnir80

thanks for the help i used P^2/a^3 = 4 pi^2/ MG to get the mass

ok so i got the reduced mass now i know that the formula for reduced mass is m1 + m2 / m1m2 but i don't really know where to go from here what I am having trouble understanding is where the parallax and ratio of distances comes in

Homework Statement we are looking at two stars in the eridani system, eri B and eri C. the period of the system is 247.9 years. the system's measured trigonometric parallax is 0.201 arcseconds and the tru angular extent to the semimajor axis of the reduced mass is 6.89". the ratio of...

sorry but how do you know they have antisemitic media, classic-style antisemitic cartoons? and only the ahmadinejad denies it not the government

Homework Statement a 5.0 mm-diameter proton beam carries a total current of 1.5mA. the current density in the proton beam, which increases with distance from the center, is given by j=j(edge)(r/R), where R is the radius of the beam and j(edge) is the current density at the edge. a) how many...

thanks allot for the help

Homework Statement the wire in the image below has a linear charge density \lambda . what is the electric potential at the center of the semicircle? http://img18.imageshack.us/img18/5139/physicsproblem.jpg Homework Equations The Attempt at a Solution i know that the potential from the semi...

Homework Statement a long, thin rod of mass M and length L is standing stright up on a table. its lower end rotates on a frictionless pivot. a very slight push causes the rod to fall over. as it hits the table, what are (a) the angular velocity and (b) the speed of the tip of the rod...

v=\omegar right? but we don't have the radius of the sphere or do we....?

Homework Statement a hollow sphere is rolling long a horizontal floor at 5 m/s when it comes to a 30 degree incline. how far up the incline does it roll before reversing direction?Homework Equations The Attempt at a Solution it seems like conservation of energy would work best for this problem...

im having problems dealing with the angle of the pendulum as it spins if we have the y-axis in the direction of centrifugal force the sum of the forces would be: ma = 400N - mgCos(angle) could i consider the ball when its at a 90 degree angle to get rid of that thing and at what point in...

Homework Statement a 20 kg wood ball hangs from a 2.0 m long wire. the maximum tension the wire can withstand without breaking is 400 n. a 1.0 kg projectile traveling horizontally hit and embeds itself in a the wood ball. what is the largest speed this projectile can have without causing the...

Homework Statement a small ball slides , with constant speed (a\theta tangential acceleration = 0) , around a horizontal circle at height h inside a firctionless, hemispherical bowl of radius R. derive a formula for the balls angular velocity \omega in terms of the radius of the radius of the...

Homework Statement a 10.2 kg weather rocket generates a thrust of 200N. the rocket ,pointing upwards, is clamped to the top of a vertical spring, whose spring constant is 500N/m and is anchored to the ground a)initially before the engine is ignited the sits at rest on top of the srping. how...

Homework Statement a 100g block on a frictionless table is firmly attached to one end of a spring with k = 20 N/m. the other end of the spring is anchored to the wall. a 20g ball is thrown horizontally toward the block with a speed of 5.0 m/s. assuming that the collision is perfectly inelastic...