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    What is the size of the net electric force on the 1.0 nC charge at the bottom of the figure? Show all of your work on your paper.

    A metal rod A and a metal sphere B, on insulating stands, touch each other as shown. They are originally neutral. First, a positively charged rod is brought near (but not touching) the far end of A. Then, while the charged rod is still close, A and B are separated. Finally, the charged rod is then withdrawn.   At the end, the charge on the rod and sphere are _______________. You do NOT need to show your work or explain your reasoning.

    An electron is moving at 7.9 x 105 m/s through a 24 μT magnetic field, as shown. What is the magnetic force on the electron? Show all of your work. [answer]

A small object is 28 cm in front of a converging lens that has a 16 cm focal length.   a. On your paper, draw the ray diagram with the three special rays, labeling the object position, image position, and focal points.   b. With the appropriate equation(s), calculate the image position and height. Show all of your work. Type both the value, with units if applicable, into the answer box.           Image position [position]           Image magnification [magnification]   c. Is the image real or virtual? [realvirtual] d. Is the image inverted or upright? [invertedupright] e. Is the image smaller or larger than the object? [smallerlarger]

A 3.8 V potential difference is applied between the ends of a 0.55 mm diameter, 42 cm long wire. The wire is made of nichrome, which has a resistivity of 1.5 x 10-6 Ω∙m. What is the current in the wire? Show all of your work.

A pendulum is pulled to the side and released. The mass swings to the right as shown. The diagram shows positions for half of a complete oscillation. You do NOT need to show or explain your work for this question.     a. At which point or points is the speed the greatest? [parta] b. At which point or points is the speed zero? [partb] c. At which point or points is the potential energy the greatest? [partc] d. At which point or points is the kinetic energy the greatest? [partd]  

In the previous question about the motion detector, how long does it take for a pulse that reflects off an object 5.5 m away to make a round trip? Show all of your work.

  The figure shows the position-versus-time graph of a particle in simple harmonic motion. Its amplitude is 4.8 cm. What is the maximum acceleration of the object?  

  A 3.25 m long string is fixed at both ends and tightened until the wave speed is 52.5 m/s.   a. What is the mode number? [mode] For parts b, c, and d, using three significant figures, type both the number and the units into the answer box. Show all of your work. b. What is the frequency of the standing wave shown in the figure? [frequency] b. What is its wavelength of the wave shown in the figure? [wavelength] c. What is its fundamental frequency? [fundamental]

Two wave pulses on a string approach each other at speeds of 1 m/s, as shown above. How does the string look at t = 3 s? It is NOT necessary to show work or reasoning for this problem.