<p>Name: Date: Circuit Calculations - Standard</p><p>Useful Information: V = I R P = I V = E t</p><p>1. Problems. Read the following problems and solve them showing all four steps.</p><p>A. A small electrical pump is labeled with a current of 3 amps and a resistance of 40 ohms. What voltage is it meant to be used at? Known Quantities Symbolic Formula Quantities “plugged in” Answer, with units</p><p>B. A nine volt battery is hooked up to a light bulb rated at three ohms. How much current flows through the bulb? Known Quantities Symbolic Formula Quantities “plugged in” Answer, with units</p><p>C. A lamp is plugged into an outlet that provides 110 V. According to an ammeter, the current is 2 amps. What is the lamp’s resistance? Known Quantities Symbolic Formula Quantities “plugged in” Answer, with units</p><p>D. A 60 W bulb operates with 120 V. How much current goes through it? Known Quantities Symbolic Formula Quantities “plugged in” Answer, with units</p><p>E. How much energy is expended in lighting a 100 W bulb for 30 minutes? Known Quantities Symbolic Formula Quantities “plugged in” Answer, with units</p><p>F. How much current is drawn by a 100 W stereo system connected to a 120 V outlet? Known Quantities Symbolic Formula Quantities “plugged in” Answer, with units 2. It’s Your Problem: Here’s something different. The problem is solved for you. Write a problem to go with the solution, and draw an appropriate diagram. Known Quantities Symbolic Formula Quantities “plugged in” Answer, with units I = 0.5 A P = I V = I2 R P = (0.5 A)2 (320 ) P = 80 W R = 320  Write your word problem here: Draw your circuit diagram here:</p><p>3. You oughta be in pictures: In the following cases, get your information from a circuit diagram. You do not need to show your work.</p><p>A. Calculate the following quantities for the circuit shown. Include units. Current: 5 ohms 1.5 V Power:</p><p>B. Calculate the following quantities for the circuit shown. Include units. Voltage: 9 kW 0.8 A Power:</p><p>C. Calculate the following quantities for the circuit shown. Include units. 5 A Power: The circuit 12 V runs for Energy: 1800 seconds.</p><p>D. Now draw a circuit of your own to match the quantities given. Then calculate the missing quantities. Draw your circuit here: Power: 1.5 W Voltage: 120 V</p><p>Current:</p><p>Resistance: 4. Plugging in Quantities. Each formula has a set of quantities with it. Rewrite the equation, “plugging in” appropriate quantities. Then find the answer to the equation and write it, with units. Formula: V = I R Quantities “plugged in”: Answer, with units: Quantities: 38 N 2 k 16 mA V Quantities “plugged in”: Answer, with units: Formula: I = R Quantities: 3 k 780 V 16 kg V Quantities “plugged in”: Answer, with units: Formula: R = I Quantities: 300 mA 32 W 120 V</p><p>5. Identifying Known Quantities and Finding Formulas. Read the following problems. In each case, write out the “known quantities.” then figure out what you can calculate from these. Write a formula that uses the known quantities to calculate the unknown. That’s it. Don’t solve the problem, at least not at this point… </p><p>A. A voltage of 120 V is applied to a person whose resistance is 100 k. Known Quantities: Symbolic Formula:</p><p>B. A current of 4 A flows when a resistor is connected across a 12-V battery. Known Quantities: Symbolic Formula:</p><p>C. A heater has a resistance of 75 k, and 2 mA of current flow through it. Known Quantities: Symbolic Formula: D. Look at the picture to get the information for this problem. Known Quantities: Symbolic Formula:</p><p>5 ohms 1.5 V</p><p>6. Problems: </p><p>7. Questions? Is there anything about this you’d like cleared up? Anything you’re wondering about?</p><p>8.</p>