Recent content by unteng10

Nevermind, got it figured out.

Homework Statement Calculate the fraction of lattice sites that are Schottky defects for cesium chloride at its melting temperature (645C). Assume an energy for defect formation of 1.86eV. Homework Equations Number of lattice sites per cubic meter (N)...

I got it. Thanks for pointing that out, its amazing how the simple mistakes always get you.

Homework Statement The quantity of a charge passing through a surface of area 2.67 cm^2 varies with time as q=q1t^3 + q2t + q3, where q1=4 C/s^3, q2=4.5 C/s, q3=9.5 C and t is in seconds. What is the instantaneous current through the surface at t=1.2s? Answer in units of A Homework...

I thought so too, but for some reason it keeps telling me my answer is incorrect.

1. A thin spherical shell of radius 6.8 m has a total charge of 7.77 C distributed uniformly over its surface. Find the electric field E 10.4 m from the center of the shell. Answer in units of N/C. ke = 8.988 * 10^9 Nm^2/C^2 2. E = ke * (Q/r^2) 3. I did (8.988 * 10^9...

Okay, so the speed would be \omega?

Homework Statement A skater spins with an angular speed of 17.4 rad/s with his arms outstretched. He lowers his arms, decreasing his moment of inertia from 43 kg/m^2 to 37 kg/m^2. Calculate his initial and final rotational kinetic energy. Homework Equations L=I\omega KE=1/2I\omega^2...

So, p=mv which would be p=(5/32)(5.4) which equals .84375. Then, F=Pf-Pi/delta T, which would be (0)-(.84375)/(.00081)-(0), which would equal -1041.67 N, but you can't have a negative force can you? Am I doing this right, or am I missing something?

Homework Statement A 5lb hammerhead, traveling at 5.4ft/s strikes a nail and is brought to a stop in .00081s. The acceleration of gravity is 32ft/s^2, What force did the nail recieve? Homework Equations The equation I have is F=Pf-Pi/delta T. Both Pf and Pi have a arrow above them...