40. Consider the system pictured in Figure P29.40. A 15.0-cm horizontal wire of

Question

40. Consider the system pictured in Figure P29.40. A 15.0-cm horizontal wire of mass 15.0 g is placed between two thin, vertical conductors, and a uniform magnetic field acts perpendicular to the page. The wire is free to move vertically without friction on the two vertical conductors. When a 5.00-A current is directed as shown in the figure, the horizontal wire moves upward at constant velocity in the presence of gravity. (a) What forces act on the horizontal wire, and (b) under what condition is the wire able to move upward at constant velocity? (c) Find the magnitude and direction of the minimum magnetic field required to move the wire at constant speed. (d) Wha

t happens if the magnetic field exceeds this minimum value?

Explanation / Answer

the magnetic force and the force of gravity.

when the magnetic force is upwards and balances the

downwards force of gravity , the net force on the wire is zero

and the wire can move upwards at constant velocity.

c)

              = mg / IL sin

              = (15*10-3 kg)(9.8 m/s2) /(5 A)(15*10-2 m)sin90

              = 0.2 T

Direction of magneticfield can be determined by right hand rule,

stretch right hand palm such that thumbs point in direction of current

and normal to palm is along force, then the fingers will be in direction offield.

direction : out of the page

d)

when the magnetic field exceeds the value we obtained , the net

Related Questions

Navigate

• Browse (All)
• Browse 4
• Subjects

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