Atest charge is placed at a distance of 2.5 × 10-2 meters from a charge of 6.4 × 10-5 coulombs. what is the electric field at the test charge? (k = 9.0 × 109 newton·meter2/coulomb2) a. 1.6 × 10-8 newtons/ coulomb b. 2.4 × 108 newtons/ coulomb c. 3.6 × 108 newtons/coulomb d. 4.2 × 108 newtons/coulomb e. 9.2 × 108 newtons/coulomb

The correct answer option is E.  9.2 × 108 newtons/coulomb.

Explanation:

We know the formula for the electric field:

E = kQ / d²

where E = electric field,

Q = the test charge in coulomb; and

d = distance.

Substituting the given values in the above formula to get:

or Newtons/Coulomb

Therefore, the electric field at the test charge is 9.2 * 10^8 Newtons/Coulomb.

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

the temperature in kelvin of 2.0 dm3 of an ideal gas is doubled and its pressure is increased by a factor of four. what is the final volume of the gas