A circuit you’re building needs an ammeter that goes from 0 mA to a full-scale reading of 50 mA. Unfortunately, the only ammeter in the storeroom goes from
a. What value of R must you use so that the meter will go to full scale when the current I is 50 mA?
b. What is the effective resistance of your ammeter?
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PHYS 212 FOR SCI+ENG W/MAST PHYS >ICP<
- A lightbulb is connected to a variable power supply. As the potential across the bulb is varied, the resulting current and the filaments temperature are measured. The data are listed in Table P28.38. a. Find R for each entry in Table P28.38, and then plot R as a function of T. b. Assume that room temperature is at 293 K. Find R0 (resistance at room temperature). Comment on your result.arrow_forwardFigure P29.45 shows five resistors connected between terminals a and b. a. What is the equivalent resistance of this combination of resistors? b. What is the current through each resistor if a 24.0-V battery is connected across the terminals?arrow_forwardWhat is the equivalent resistance between points a and b of the six resistors shown in Figure P29.70? FIGURE P29.70arrow_forward
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- In (Figure 1), R1R1R_1 = 3.00 ΩΩ, R2R2R_2 = 7.00 ΩΩ, and R3R3R_3 = 4.00 ΩΩ. The battery has negligible internal resistance. The current I2I2 through R2R2 is 3.00 A . What is the emf of the battery? Express your answer with the appropriate units.arrow_forwardFind (a) the equivalent resistance of the circuit in Figure P28.60, (b) the potential difference across each resistor, (c) each current indicated in Figure P28.60, and (d) the power delivered to each resistor.arrow_forward
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