Recent content by Ampere

Homework Statement Figure 26-30 shows a swimmer at distance D=35m from a lightning strike to the water, with current I=78kA. The water has resistivity 30 Ohm*m, the width of the swimmer along a radial line from the strike is 0.7m, and his resistance across that width is 4 kOhm. Assume that the...

Yes, I meant (2.5 L - 5.0 L). Thanks for the confirmation!

Homework Statement Heat flows into an ideal gas at a constant volume. The pressure increases from 1.5 atm to 5.5 atm. Next the gas is compressed at constant pressure from 5.0 L to 2.5 L and goes back to its original temperature. 1.What is the total work done on the gas in the process...

Awesome, thanks.

Sure. Align A along the +x axis, with B at 40 degrees above that. Then: Ax = 8 Ay = 0 Bx = Bcos(40) By = Bsin(40) So Rx = 8+Bcos(40) Ry = Bsin(40) The magnitude of the resultant R would be sqrt(Rx^2 + Ry^2), which is equal to 20, so 20 = sqrt((8+Bcos(40))^2 + (Bsin(40))^2). Solving for B...

Homework Statement The resultant of vectors A and B has a magnitude of 20 units. A has a magnitude of 8 units, and the angle between A and B is 40 degrees. Calculate the magnitude of B. Homework Equations Trig, resolving vector components. The Attempt at a Solution I worked out...

Yep.

What do you think - does it look like the formula depends on the radius?

Okay that makes sense. What you're saying is that, to prevent oscillation, someone must have "guided" the charges to the 2cm equilibrium position, and work was done as they did that. Thanks for the help. I hadn't thought of it that way.

You can use the tangent to find them, since you know the length of the adjacent and opposite sides.

What are you using as the masses? One of them would be the mass of a proton; the other would be the mass of an electron.

Sketch right triangles involving S and T and use cosine and sine to find each vector's x and y components. Then add the components.

"Your missing energy is the work done on the external agent as you ease up on the force." I don't understand this - any physics problem would require an "external agent" to set it up and/or hold it in place. Consider block-and-pulley problems. Before releasing the block, you would need to hold...

Try dq = lambda*r*d(theta) and integrating in polar coordinates. You will integrate over a half circle, i.e. from 0 to pi. R=r=constant because of the semicircle shape. You can use geometry to find the radius since the length of the rod is 1/2 the circumference of a full circle.

Homework Statement An unstrained horizontal spring has a length of 0.32 m and a spring constant of 220 N/m. Two small charged objects are attached to this spring, one at each end. the charges on the objects have equal magnitudes. Because of these charges, the spring stretches 0.020 m, relative...