physics

Two wires are made of the same material. The first wire dissipates power P with a current of I. If the second wire is 3 times as long and has twice the diameter, what will the current need to be through the second wire to dissipate the same power P as the first wire?

A particle enters a magnetic field with velocity v. Find the mass of the particle in terms of v, B, and x.

  1. 👍 0
  2. 👎 0
  3. 👁 140
  1. Using the idea of resistors in series and in parallel, we conclude that:

    resistance is proportional to length, and
    inversely proportional to the area.

    That should be sufficient to solve the first problem.

    1. 👍 0
    2. 👎 0
    posted by MathMate

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics

    Two spherical conducting wires A and B are connected to the same potential difference. Wire A is three times as long as wire B, with a radius double that of wire B and resistivity doubles that of wire B. What is the ratio power

    asked by Anonymous on November 13, 2013
  2. physics

    Two spherical conducting wires A and B are connected to the same potential difference. Wire A is three times as long as wire B, with a radius double that of wire B and resistivity doubles that of wire B. What is the ratio power

    asked by Anonymous on November 14, 2013
  3. Electricity help needed please

    Two spherical conducting wires A and B are connected to the same potential difference. Wire A is three times as long as wire B, with a radius double that of wire B and resistivity doubles that of wire B. What is the power

    asked by Abdu on November 15, 2013
  4. physics

    Two spherical conducting wires A and B are connected to the same potential difference. Wire A is three times as long as wire B, with a radius double that of wire B and resistivity doubles that of wire B. What is the power

    asked by Anton on November 13, 2013
  5. physics

    Consider two copper wires with the same cross-sectional area. Wire A is twice as long as wire B. How do the resistivities and resistances of the two wires compare? CHECK ALL THAT APPLY Wire A and wire B have the same resistance.

    asked by Anonymous on February 7, 2014
  1. Physics ||

    Q.1. Two wires each of length 40 m and diameter 2.6 mm, are connected in series. A potential difference of 50 V is applied between the ends of the composite wire. The resistances the wires are 0.13 Ω and 0.75 Ω, respectively.

    asked by Meemee.meme on June 4, 2014
  2. Physics; help please :)

    Two wires made of the same material of density 7240 kg/m3 and having the radius in the ratio 1:2 but the same length 1.54 connected together and stretched by a force of 540 N. If the speed of a transverse wave through the thinner

    asked by Celine on September 4, 2013
  3. Physics

    A piece of Nichrome wire has a radius of 8.0 10-4 m. It is used in a laboratory to make a heater that dissipates 2.00 102 W of power when connected to a voltage source of 120 V. Ignoring the effect of temperature on resistance,

    asked by Mary on September 7, 2007
  4. Physics

    Two current carrying wires cross at right angles as indicated in the figure. If the wires are not restrained, what statement best describes the motion of the wires? Hint: To help you visualize the situation, draw first the

    asked by mm. on March 15, 2010
  5. Physics

    Three wires lie in a plane, placed parallel to one another and equally spaced by 0.20 m. If the wires are oriented up and down on the page, the right-hand wire carries 100 A to the top, the middle wire 300 A to the bottom, and the

    asked by Anonymous on March 17, 2016

More Similar Questions