Ohm's law - math problems

Ohm's law states that the current through a conductor (or resistor) between two points is directly proportional to the voltage across the two points. Introducing the constant of proportionality, the resistance, it arrives at the usual mathematical equation I = U/R or I=V/R

Number of problems found: 21

  • Three resistors
    SPP You have to connect three identical resistors with 12 Ohm resistances so that you gradually get the resulting resistance a) 36 Ohm, b) 4 Ohm, 18 Ohm. Draw a diagram of each circuit.
  • Lowest voltage
    inSeries Three resistors with resistors R1 = 10 kΩ, R2 = 20 kΩ, R3 = 30 kΩ are connected in series and an external voltage U = 30 V is connected to them. On which resistor is the lowest voltage?
  • Resistors
    resistors Two resistors connected in series give the resulting resistance 245Ω and 60Ω in parallel. Determine the resistance of these resistors.
  • Two resistors
    resistor Two resistors 20 Ω and 60 Ω are connected in series and an external voltage of 400 V is connected to them. What are the electrical voltages on the respective resistors? Please comment!
  • Mains voltage
    bulb How much electric current flows through the appliance with a resistance of 40kΩ, which is connected to the mains voltage (230 V)?
  • Closed circuit
    voltemeter In a closed circuit, there is a voltage source with U1 = 12 V and with an internal resistance R1 = 0.2 Ω. The external resistance is R2 = 19.8 Ω. Determine the electric current and terminal voltage.
  • Current in the conductor
    ohms-law Calculate the current in the conductor (in mA) if it is connected to a 4.5 V voltage source and its resistance is 20 (ohm).
  • Filament of bulb
    bulb The filament of bulb has a 1 ohm resistivity and is connected to a voltage 220 V. How much electric charge will pass through the fiber when the electric current passes for 10 seconds?
  • Two resistors
    two_resistors Two resistors when they give 25 ohms in series and 4 ohms in parallel what the values of
  • The bulb
    bulbs What is the resistance of a filament lamp when it is connected to a 9V battery and has a current of 120 mA?
  • Resistance of the resistor
    Elektrárna The resistor terminals have a voltage of 20 V and a current of 5 mA is passed through. What is the resistance of the resistor?
  • Resistance
    bulb Determine the resistance of the bulb with the current 200 mA and is in a regular lamp (230V).
  • Coil as a girl
    tlmivka_TL1 The electrical resistance of the copper wire coil is 2.0 ohms. What current runs through the coil when the voltage between the terminals is 3.0 V?
  • Resistance - ohms
    resistor If the resistance of the first resistor is 300 ohms and the resistance of the second resistor is 100 ohms. What is the resulting resistance?
  • Circuit voltage
    resistor Calculate the closed circuit voltage. Calculate the power on the resistors. R1 = 30 ohms, R2 = 10 ohms. I = 0.1A. U =?. The resistors are connected in series, one after the other.
  • Transformer
    trafo Solve the textbook problems - transformer: a) N1 = 40, N2 = 80, U2 = 80 V, U1 =? b) N1 = 400, U1 = 200 V, U2 = 50 V, N2 =?
  • Electric input power
    resistor Solve problems related to electric power: a) U = 120 V, I = 0.5 A, P =? b) P = 200 W, U = 230 V, I =? c) I = 5 A, P = 2200W, U =?
  • Copper winding
    ohms-law Calculate the current flowing through the copper winding at an operating temperature of 70°C. Celsius, if the winding diameter is 1.128 mm and the winding length is 40 m. The winding is connected to 8V.
  • The bulbs
    resistor The bulbs are connected serially two bulbs and one resistor. Each bulb has a resistivity of 100 ohms and resistor of 60 ohms The voltage source in the circuit is 24 volts. Do you know what voltage to measure on individual appliances?
  • R1+R2 in parallel
    resistor The resistance ratio of the first and second resistors is 3: 1 and the current flowing through the first resistor is 300 mA. What current flows through the second resistor (resistors connected in parallel)?

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