Evaluate charges

(See attached file for full problem description) --- a) Two charges, Q1 and Q2 are separated by distance r. State Coulomb’s law and write down the force each charge. Explain the condition for a repulsive force and for an attractive force. b) What is the magnitude and direction of the force between two charges of -10µC and + 40 µC set 100 mm apart? Comment on your answer. Sketch the E-field and equipotentials associated with this charge system. c) Charges of Q1 = -10 pC and Q2 = -20 pC are placed 200 mm apart. At what point the force on a test charge of 1 C be zero? 1 pC = 10-12C. The constant = 9 x 109 m/F, where ε0 is the permittivity of free space. ε0= 8.85 x ... click for more

Magnetic resonance imaging (MRI)

Magnetic resonance imaging (MRI) is a medical technique for producing pictures of the interior of the body. The patient is placed within a strong magnetic field. One safety concern is what would happen to the positively and negatively charged particles in the body fluids if an equipment failure caused the magnetic field to be shut off suddenly. An induced emf could cause these particles to flow, producing an electric current within the body. Suppose the largest surface of the body through which flux passes has an area of 0.032 m2 and a normal that is parallel to a magnetic field of 1.5 T. Determine the smallest time period during which the field can be allowed to vanish if the magnitude of t... click for more

Magnetic fields

The solar wind is a thin, hot gas given off by the sun. Charged particles in this gas enter the magnetic field of the earth and can experience a magnetic force. Suppose a charged particle traveling with a speed of 9.0 X 10^6 m/s encounters the earth's magnetic field at an altitude where the field has a magnitude of 1.2 X 10^-7T. Assuming that the particle's velocity is perpendicular to the magnetic field, find the radius of the circular path on which the particle would flow if it were a proton.

Magnetism

The earth’s magnetic field, like any magnetic field, stores energy. The maximum strength of the earth’s field is about 7.0 x 10^-5 T. Find the maximum magnetic energy stored in the space above a city if the space occupies an area of 5.0 x 10^8 m2 and has a height of 1500 m.

Griffiths 2.11 Electrostatics

Griffiths problem 2.11, an applicatoin to Gauss's Law inside and outside of a spherical shell of uniform charge.