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1) A proton is released from rest in a region of space with a nonzero electric field. As the proton moves, does the electric potential energy of the system increase, decrease, or stay the same? Explain.
2) How far must the point charges q1 = +7.22 uC and q2 = -26.1 uC be separated for the electric potential energy of the system to be -126J?
3) To operate a given flash lamp requires a charge of 32 uC. What capacitance is needed to store this much charge in a capacitor with a potential difference between its plates of 9.0V?
4) The separation of b/w the plates of of a parallel plate capacitor is doubled and the area of the plates is halved. How is the capacitance affected?
5) A 75W lightbulb operates on a potential difference of 95V. Find (a) the current in the bulb and (b) the resistance of the bulb. (c) If this bulb is replaced with one whose resistance is half the value found in part (b), is its power rating greater than or less than 75W? By what factor?
6) A wire with a current of 2.8 A is at an angle of 36 degrees relative to a magnetic field of 0.88T. Find the force exerted on a 2.25 m length of wire.
7) Explain what happens when the angular speed of the coil in an electric generator is increased.
8) Transformer 1 has a primary current Ip and a secondary current Is. Transformer 2 has twice as many turns on its primary coil as transformer 1, and both transformers have the same number of turns on the secondary coil. If the primary current on transformer 2 is 3Ip, what is its secondary current? Explain.
2) How far must the point charges q1 = +7.22 uC and q2 = -26.1 uC be separated for the electric potential energy of the system to be -126J?
3) To operate a given flash lamp requires a charge of 32 uC. What capacitance is needed to store this much charge in a capacitor with a potential difference between its plates of 9.0V?
4) The separation of b/w the plates of of a parallel plate capacitor is doubled and the area of the plates is halved. How is the capacitance affected?
5) A 75W lightbulb operates on a potential difference of 95V. Find (a) the current in the bulb and (b) the resistance of the bulb. (c) If this bulb is replaced with one whose resistance is half the value found in part (b), is its power rating greater than or less than 75W? By what factor?
6) A wire with a current of 2.8 A is at an angle of 36 degrees relative to a magnetic field of 0.88T. Find the force exerted on a 2.25 m length of wire.
7) Explain what happens when the angular speed of the coil in an electric generator is increased.
8) Transformer 1 has a primary current Ip and a secondary current Is. Transformer 2 has twice as many turns on its primary coil as transformer 1, and both transformers have the same number of turns on the secondary coil. If the primary current on transformer 2 is 3Ip, what is its secondary current? Explain.