PHY 2049: Physics II

• Exam II is scheduled for Wednesday June 18, in class.

• Ch. 26: Current and resistance • Ch. 27: Circuits• Ch. 28: Magnetic Field Effects• Ch. 29: Field from currents.

PHY 2049: Physics II, HITT• The diagram shows a

straight wire carrying current i in a uniform magnetic field. The magnetic force on the wire is indicated by an arrow but the magnetic field is not shown. Of the following possibilities, the direction of the magnetic field is:

A. opposite the direction of the currentB. opposite the direction of FC. in the direction of FD. into the pageE. out of the page

PHY 2049: Physics II, HITT• The diagram shows a

straight wire carrying current i in a uniform magnetic field. The magnetic force on the wire is indicated by an arrow but the magnetic field is not shown. Of the following possibilities, the direction of the magnetic field is:

A. opposite the direction of the currentB. opposite the direction of FC. in the direction of FD. into the pageE. out of the page

PHY 2049: Physics II

A different problem• Electrons (mass m, charge −e) are accelerated from

rest through a potential difference V and are then deflected by a magnetic field B that is perpendicular to their velocity. The radius of the resulting electron trajectory is:

A. √(2eV/m)/ B B. B√(2eV) /m C. √(2mV/e)/BD. B√2mV /e E. none of these