Recent content by kerbyjonsonjr

Homework Statement A right triangle is shown below. The charge on the right is unknown, but the electric field shown is only in the –x direction. a. What is the unknown charge? b. What is the magnitude of the electric field? Homework Equations The Attempt at a Solution...

Homework Statement In a science museum, a brass pendulum bob swings at the end of a 15m long wire. The pendulum is started at exactly 8:00 a.m. every morning by pulling it 1.5m to the side and releasing it. Because of its compact shape and smooth surface, the pendulum's damping constant is...

I finally got it. I forgot to use m for the radius when I calculated the velocities. I redid it and finally got the correct answer of 5.01 x10^8 J. Thank you so much for taking the trouble to help me. I really appreciate it.

The final energy: 1/2(6000 kg)(503772 m/s) - 6.67 x 10^-11 (7.36 x10^22 kg)(6000 kg)/(1937000 m) = 7.6 x10^12 - 1.52 x10^10= 7.59 x 10^12 The initial energy: 1/2(6000 kg)(519732 m/s) -6.67 x10^-11 (7.36 x10^22 kg)(6000 kg)/(1817000m)= 8.1 x10^12 - 1.62 x10^10 = 8.08 x10^12 Then I would...

It would seem as though I am still doing something wrong because I am now getting a negative value again. I plugged in the value for r in meters my change in energy ended up being 7.58 x10^12 - 8.07 x10^12 which is a negative number. The only thing I did different was plug in the new r values.

Would it be the radius that needs to be in meters? Or is it something else?

Is the rest of the setup though because I am still getting an incorrect answer I have KEf-GMm/r +(KE2 - GMm/r) So I put in 1/2(6000)(50,3372) - 6.67 x10^-11(7.36 x10^22)(6000)/(1937)= -7.6 x10^12 Then the other half is 1/2(6000)(519732) -6.67 x10^-11(7.36 x10^22)(6000)/(1817)= -8.1...

Alright, so would I solve for change in E by saying KEf + Uf -(KEi + Ui) ? Is U equal to GMm/r?

Homework Statement A 6000 kg lunar lander is in orbit 80 km above the surface of the moon. It needs to move out to a 200 km -high orbit in order to link up with the mother ship that will take the astronauts home. How much work must the thrusters do? Homework Equations...

Homework Statement What is the x and y coordinates of the center of mass for the uniform steel plate shown in the figure ? Homework Equations x=1/M \sum x dm The Attempt at a Solution I am not really sure how to being this one. Mass isn't given so I am not sure where to start. I...

Homework Statement A 2.5 kg wood block hangs from the bottom of a 1.0 kg, 1.2 m long rod. The block and rod form a pendulum that swings on a frictionless pivot at the top end of the rod. A 12 g bullet is fired into the block, where it sticks, causing the pendulum to swing out to a 33 angle...

If you look at the picture in the attachment you will see that the box keeps moving after it goes up the incline and then it becomes a trajectory problem.

Homework Statement The spring in the figure has a spring constant of 1300 N/m . It is compressed 13.0cm , then launches a 200g block. The horizontal surface is frictionless, but the block's coefficient of kinetic friction on the incline is 0.180. What distance does the block sail through...

got it now! thanks for the help! I messed up. It should have been the final minus the initial. So it's 2v-2(4)=6 which gets me v= 7 m/s. Thanks for the help!

Homework Statement A 2kg object is moving to the right with a speed of 4 m/s when it experiences an impulse of 6 Ns . Homework Equations mv+mv=mv The Attempt at a Solution Since the impulse is just the change in momentum I put in 2(4)+2v=6 so wouldn't v be -1?