# Search results

1. ### Archived What is the equivalent capcitance of this circuit! - Figured it out.

What is the equivalent capcitance of this circuit! -- Figured it out. I have a Physics final exam in 2 hours and I'm re-reviewing things.... This problem DOESN'T make any sense!! 17. If C1 = 2 F, C2 = 3 F, C3 = 5 F, C4 = 6 F, the equivalent capacitance of the circuit is: A. 8.5 F is...
2. ### Index of Refraction Concept - Extremely Confusing

I have just a few more questions regarding index of refractions and reflections... 8. A fly is 10 cm above the surface of a pond. How high above the water does the fly appear to a fish directly below (nair = 1, nwater = 1.333)? (A) 10 cm (B) 7.5 cm (C) 13.3 cm (D) 12.5 cm (E) fish cannot see...
3. ### Stressed about Physics Exam! Help with refractive index concept!

7. The figure shows the path of a portion of a ray of light as it passes through three different materials. What can be concluded concerning the refractive indices of these three materials. (A) n1 < n2 < n3 (B) n1 > n2 > n3 (C) n3 < n1 < n2 (D) n2 = n1 > n3 (E) n1 = n2 < n3 The...
4. ### Mirrors, Polaroid Films, Light/Wavelength help needed

:(:(:( Please ease my aching soul by helping me with this... I submitted this assignment online and I don't know the answers yet or however many I got wrong. I chose 45 because I know unpolarized light becomes this after going through a polarizer: That single line is 180º, so I did...

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6. ### Trouble determining the slope of the graph!

For the slope, I got 0.4532 and for B, I got 74.09, but they're both wrong! And my excel program keeps crashing everytime i try to print screen it! This is really urgent and I don't know who else to turn to because this is due very very soon and I'm desperate!! Also, what about this one:
7. ### Determining the direction of current on a wire?

In each of parts (a), (b), and (c) of the figure below, find the direction of the current in the wire that would produce a magnetic field directed as shown. part (a) right to left part (b) out of the page part (c) lower left to upper right Ughhhhh So, the right hand rule...
8. ### WHY does the sign for B1 and B2 keep CHANGING in this Bnet equation?

The two wires shown in the figure below are separated by d = 8.0 cm and carry currents of I = 4.85 A in opposite directions. d = 8 cm = 0.08 m d = 8 cm = 0.08 m r = 0.08/2 = 0.04 m 2d = 21.6 cm I (up) = 4.80 A I (down) = 4.80 A (a) Find the magnitude and direction of the net magnetic field...
9. ### Right Hand Rule doesn't work for this problem?

Right Hand Rule doesn't work for this problem??? Consider an electron near the Earth's equator. In which direction does it tend to deflect if its velocity is directed in each of the following directions? I DON'T get this! I know they're basically saying this: Velocity of electron...
10. ### Help with determining the direction of induced currents

2. Three loops of wire move near a long straight wire carrying a current as in the following figure. (a) What is the direction of the induced current, if any, in loop A? a. clockwise b. counterclockwise c. No current is induced. (ANSWER) WHY IS "C" THE ANSWER???? I don't...
11. ### Omggg Determining voltage between point a and b given R = 40 ohms

Omggg :( Determining voltage between point a and b given R = 40 ohms This is what I did for part A: 1) ΔVrms = Vmax(1/√2) ΔVrms = (145)(0.707) ΔVrms= 102.53 2) Ztotal = √[R² + (XL - XC)²] XL = 2πfL XL = 2π(40)(185 x 10^-3) XL = 46.49 XC = 1/2πfC XC = 1/[2π(40)(65 x 10^-6) XC =...

How do I go about solving this? Whenever I see a capacitor diagram/an image like this i always freak about because 1) I don't know what to ask myself when I see it 2) I'm not sure I know what's going on - other than the fact the the | | means: +| |- I don't know what the squiggly lines...
13. ### Complcated Chemistry Reaction - impossible?

Complcated Chemistry Reaction - impossible?? Help :( My notes say: Step 1 is a 221 reaction. If peroxides are used in your version, then the anti-Markovnikov bromide is formed. If your version had only HBr, the the Markovnikov bromide is formeed. Step 2 creates organolithium or Grignard...
14. ### My brain has been shocked by this problem dealing with charges and Coulombs law

My brain has been shocked by this problem dealing with charges and Coulombs law :( This is what I did... F = k*q1*q2/r^2 F = [ (8.99 * 10^9)(4.9 * 10-9)(6.0 * 10^-9) ] / (0.295)^2 F = 0.000000264 / 0.087025 F = 0.0000003034 F = 3.034 * 10^-7 N F = k*q1*q3/r^2 F = [ (8.99 *...
15. ### Horizontal Spring Pulled from Equilibrium?

I don't necessarily understand the explanation given to the solution. Is it basically saying: A (valley) --> 0 (equilibrium) --> -A (valley) --> 0 (equilibrium) --> A (valley)?
16. ### Are these three things DEPENDENT on Amplitude?

So if Period is the only thing that isn't dependent on amplitude, then that must mean Energy (PE = 1/2 k A2), maximum acceleration, and speed is dependent on amplitude?
17. ### What is the mass's total acceleration at the bottom of its swing?

The answer to this is up (d). But why? Is it because centripetal acceleration is pointing to the center of the pivot?
18. ### Help with Potential Energy vs Kinetic Energy and finding final velocity!

Ok before we get to number 3, I need to show you what I did for number 2 because this is kind of a two-part problem: PEinitial + KEinitial = PEfinal + KEfinal mgy + (1/2)mvi2 = (1/2)mvf2 gy + (1/2)vi2 = (1/2)vf2 (9.81)(10) + (1/2)(102) = vf2/2 98.1 + 50 = vf2/2 148.1 = vf2/2 2(148.1) = vf2...
19. ### Help with Kinetic Energy concept of two masses that move the same distance

Help with Kinetic Energy concept of two masses that move the same distance!! I don't understand why the answer to this is B :( Because KE = (1/2)mv2, if they move the same distance and have DIFFERENT masses, the kinetic energies would be different no?
20. ### Help with finding the coefficient of kinetic friction!

Ok so I tried making myself a free-body diagram but I reached a dead end.. Step 1) fkinetic = μkn fkinetic = μk(251) fkinetic / 251 = μk Step 2) Fx: T1 Fy n = (m)(g) = 251 N 120.5 N Step 3) ƩFx = m(-a) since it's moving the left or ƩFx = 0 (since it's moving at CONSTANT velocity) ƩFy = ma...
21. ### Find the tension T of the two blocks. I think I'm doing something wrong

Find the tension T of the two blocks. I think I'm doing something wrong :( T1 = m1g = (2)(9.81) = 19.62 T2final = T2 + T1 = m2g + m2g = (3)(9.81) + (2)(9.81) = 29.43 + 19.62 = 49.05 I did something wrong. :( Help?
22. ### Real quick help needed with KINEMATIC EQUATION

So I'm given... In the y-direction vo = 0 m/s vf = 7.5 m/s (is the speed of the ball thrown straight up) g = -9.81 m/s2 (when it falls back down) yo = 0 m yf = 1.5 m (at this height above the ground, the bat connects with the ball) t = ? I tried doing this... yf = yo + vyot +...
23. ### What is the moment of inertia of this rotating object?

KErotational = (1/2)Iω2 420 = (1/2)Iω2 420 = (1/2)I(402) 420/(402) = (1/2)I 0.2625 = (1/2)I 2(0.2625) = I 0.525 = I 0.53 = I
24. ### Sum of Torque vs. Conservation of Angular Momentum! Quick help needed!

Number 11) This is what I did: Ʃτ = F2r2 + F1r1 = 0 (195)(7) + F1(0.7) = 0 F1(0.7) = -(195)(7) F1 = -1365/0.7 F1 = -1950 N F1 = 1950 N Is that answer right? Number 12) This is what I did: Since this is a massless rod and the location of the axis is through the end, I = ML2 Linitial =...
25. ### Elevetor and acceleration as elevator goes up - algebra involved?

Period for pendulum is T = 2π√(L/g) When a pendulum is in an elevator and it goes up T = 2π√(L/9.8+a) At rest: T = T0 Elevator moves upward with constant acceleration a = 3g T = 2π√(L/9.8+3g) So I have to solve for T0 T0 = 2π√(L/9.8+a) = 2π√(L/9.8+3g) T0 = (√(L/9.8+a))2...
26. ### Which of the following things DOESN'T change if you double this?

Why is the answer to this period? I know T = 2π√(L/g) But I don't know how period doesn't change if you double amplitude, when amplitude isn't even in the equation (?)
27. ### Coke bottle on another planet, involving harmonics and speed

This is what I tried doing, but I ended up getting an answer that isn't listed above 1. frequency = speed/wavelength 2. On Earth 480 Hz = (343 m/s)/wavelength wavelength = 343 / 480 wavelength = 0.714 is the wavelength for the Coke bottle 3. On Earth 2 Since they already gave me...
28. ### Help with oscillating spring concept?

Is it acceleration? I found this graph online: Would the answer be acceleration?
29. ### Quick help need with finding the MAGNITUDE of the TORQUE of this wrench

I tried using Frsin θ (270.756)(46 cm)sin (68) but I got 11547.86 And got it wrong... And then I tried doing. 101.426982807+251.040591727 = 352.4 N*m but I got it wrong. ^ I don't remember how I did that but it was saved in my notes. Help?
30. ### I need to get a 100 on this last Physics lab assignment, but I can't get this rod

I need to get a 100 on this last Physics lab assignment, but I can't get this "rod" ...problem :( Help would be appreciated (a) L1 = (65 cm)/2 = 32.5 cm "CORRECT" (b) [(149 kg)(1) + (149 kg)(65 cm) + (149 kg)(65 cm + 32.5 cm)] / (3)(149 kg) = (149 + 9685 + 14527.5) / (447) =...