help A conducting rod of length l moves on two horizontal frictionless rails, as

Question

help

A conducting rod of length l moves on two horizontal frictionless rails, as in the figure below. A constant force of magnitude 5.00 N moves the bar at a uniform speed of 4.00 m/s through a magnetic field that is directed into the page. What is the current in an 14.00 Ohm resistor R? Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. What is the rate of energy dissipation in the resistor? W What is the mechanical power delivered by the constant force? W

Explanation / Answer

a . Change in magnetic flux E = Blv

Magnetic force on the wire ll be F = ILB sin 90 = ILB

also

I = E/R = BLv/R = Fv/I

hence

I = sqrt (Fv/R)

= sqrt(5*4/14) = 1.195 A

b. Power = I^2*R = (1.195)^2*(14) = 20 Watt

c. also Power = dw/dt

  

= F* ds/dt

= (5)*(4)cos0 = 20 watt

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.