Physical Science

a vacum tube can be used to

change alternating current into direct current

increase the strength of a signal

turn a current on or off

all of the above

  1. 👍
  2. 👎
  3. 👁

    1. 👍
    2. 👎
    Ms. Sue

Respond to this Question

First Name

Your Response

Similar Questions

  1. science

    The potential difference measured across a coil is 20 V when a direct current of 2 A is passed through it. With an alternating current of 2 A at 40 Hz, the p.d. across the coil is 140 V. If the coil is connected to a 230 V, 50 Hz

  2. physics

    if one resistor is removed from a parallel circuit, the total current will 1) decrease b) increase c) remain the same and the current flowing through each of the remaining branches ____________________. removing one resistor makes

  3. science help

    What would happen to the current model of the atom if new information about its structure is discovered in the future? A. The current atomic model would be revised. B. The current atomic model would be strengthened. C. The current

  4. Circuits2

    An alternating current and a direct current flows simultaneously in the same conductor. if the effective value of the alternating current is 5A and the direct current is 10 A, what will an AC ammeter read when connected in the

  1. Science

    If the current in a wire is directed upward, what is the direction of the magnetic field produced by the current? A. counterclockwise B. clockwise C. in the same direction as the current D. in the opposite direction to the current

  2. Science

    Which option most accurately describes alternating current? current that moves in one direction throughout a circuit current that moves in one direction until it reaches the battery, then moves in the other direction current that

  3. Math... with complex numbers

    Complex numbers are often used when dealing with alternating current (AC) circuits. In the equation V = IZ, V is voltage, I is current, and Z is a value known as impedance. If V = 1+i and Z=2-$, find I.

  4. physcial science

    Which of the following statements about Ohm’s Law is true? A. Increasing the voltage decreases current. B. Keeping the same voltage and decreasing resistance decreases the current. C. Ohm’s law relates power, current and

  1. Physics

    Tracy swims across a stream of width 40.0 m in 33.0 s when there is no current. She takes 59.0 s to cover the same distance when there is a current. Find the speed of the river current.

  2. physics

    a d'arsonval meter movement deflects to 0.8mA. what is the peak value of the alternating current if the instrument uses full-wave rectification?

  3. Physics

    Which material provides resistance to the flow of electrons? A. Silver B. Saltwater C. Salt crystals D. Copper A circuit has a resistance of 50.0 ohms. What is the voltage needed to generate a current of 0.02 amps? A. 100 volts B.

  4. 12th Calculus

    suppose that at any tiem t(sec) the current i(amp) in an alternating current circuit is i=2cost+2sint. What is the peak (largest magnitude) current for this circuit?

You can view more similar questions or ask a new question.