An aluminum rod with a mass m slides on parallel horizontal brass rails, a distance L apart, and carries a current of I. The coefficient of kinetic friction between the rod and rails is ?. What vertical, uniform magnetic field is needed to keep the rod moving at a constant speed? (Enter the magnitude. Use any variable or symbol stated above along with the following as necessary: g.)

Consider a long, horizontal Large Wire with current of 10 A running through it. We want to levitate a horizontal, thin, 0.50 m length of wire above it. If the thin wire has a mass of 10 grams, and a current of 300 mA, how far above the Large Wire will it hover (net force of zero) due to magnetic and gravitational forces? A. If the thin wire hovers above the Large Wire due to their magnetic fields, are their currents going the same direction, or opposite directions. Explain. B. Draw a diagram and label the directions of currents, and all other relevant quantities and vectors. C. Find the distance above the Large Wire the small thin wire will hover (net force of zero). D. Would your answers to parts A and C change if we wanted to find a distance below (rather than above) the Large Wire that the smaller thin wire could hover, due to their magnetic fields. Explain. Don't calculate any values but draw a new diagram and explain how this situation compares to the problem above.

A loop of wire in the shape of a rectangle of width w and length L and a long, straight wire carrying a current I lie on a tabletop as shown in the figure below. (a) Determine the magnetic flux through the loop due to the current I. (Use any variable stated above along with the following as necessary: H. and r.) (b) Suppose the current is changing with time according to I = a + bt, where a and b are constants. Determine the magnitude of the emf that is induced in the loop if b = 17.0 A/s, h = 1.00 cm, w = 19.0 cm, and L = 1.25 m. V (c) What is the direction of the induced current in the rectangle? O clockwise O counterclockwise O The magnitude is zero.

Please answer this within 30 mins ! I will upvote !

Check my work 2 1 points The magnetic field in a hospital's cyclotron is 0.410 T. Find the magnitude of the magnetic force on a proton with speed 1.20 × 107 m/s moving in a plane perpendicular to the field. N Skipped

A particle of mass “M” and charge “+Q” Travels at a velocity “V” in a plane perpendicular to a Magnetic Field of magnitude “B” as shown in the Picture. The particle will experience motion on a circular path. (not the question just context, also the pic is for probelm 1.) Assume similar conditions as problem 1 but now the proton, moves along the magnetic field undeflected. This new behavior can only be explained if there exist an external electric field in addition to the magnetic field. What is the magnitude and direction of such field? (you can disregard gravity) (prob 2 is the question:) sorry if its confusing)

Uniform magnetic field points perpendicular out of the page. A wire carrying current I is placed in the magnetic field. What is the direction of magnetic force on electron #1 moving in the direction of the arrow next to it?