Practice Problems

See the figure. The net force on the 1 nC charge is zero. What is q?

A) zero B) 1.5nC C) 0.68nC D) 5nC

A concave mirror with a radius of 30 cm creates a real image 40 cm from the mirror. What is the object distance?

A) 24 cm B) 5.0 cm C) 10 cm D) 70 cm

If a current is flowing with a value of 5.9 A, how much electron charge passes any single point in 25 seconds?

A) 2.3 x 1020 e B) 9.2 x 1020 e C) 1.9 x 1020 e D) 1.5 x 1020 e

If the force between two charges increases by a factor of 16 because the charges are moved closer together, how much closer are they moved?

A) 8 B) 16 C) 2 D) 4

Starting from rest, a proton falls through a potential difference of 2700 V. What speed does it acquire?

A) 2.4 × 105 m/s B) 7.2 × 105 m/s C) 3.6 × 105 m/s D) 4.8 × 105 m/s

A long, straight wire carries a current of 2.5 A. Find the magnitude of the magnetic field 25 cm from the wire.

Which of the equations here is valid for the circuit shown?

A) 4 - I1 + 4I3 = 0 B) 6 - I1 - 2I2 = 0 C) 2 - 2I1 - 2I2 - 4I3 = 0 D) -2 - I1 + 4 - 2I2 = 0

A flux of 4.0 × 10-5 Wb is maintained through a coil for 0.50 s. What emf is induced in this coil by this flux?

A) 2.0 x 10-5 V B) 4.0 x 10-5 V C) No emf is induced in this coil. D) 8.0 x 10-5 V

Estimate the average power output of the Sun, given that about 1350 W/m2 reaches the upper atmosphere of the Earth. The distance from the Sun to the Earth is 1.5 × 1011 m.

A) 1 × 1026 W B) 4 × 1026 W C) 2 × 1026 W D) 3 × 1026 W

A beam of light traveling in air is incident on a transparent plastic at an angle of incidence of 50o. The angle of refraction is 35o. What is the index of refraction of the plastic?

A) 1.56 B) 1.67 C) 1.43 D) 1.34

Folks please review and study these examples I have here as you will need to understand this for the practice problems.

These law are applicable to D.C. Circuits as there is no promise they can always be applied to A.C. circuitry. Why? Unlike D.C. circuits that could have resistors that occur voltage drops across them, or even capacitors that would have a finite time to charge before reaching a steady state or equilibrium state, A.C. circuitry has inductors that rely on the alternating current to produce magnetic energy. Since all this is time dependent it would be very difficult to write equations as we do that clearly have no time dependence to them. Calculus would be required to produce what we call ordinary differential equations which describe rates of change of functions and variables that may depend on more than one or the other of them in a system. In that case we call them partial differential equations. See the attached file. Thanks.

Practice problems -    SHOW ALL WORK for ALL problems (even the multiple choice ones) on the practice.  .  See Kirchoff's Laws. Solve electric loop circuits using the two rules. There are out two examples for you to review. Do this BEFORE you try to solve the Kirchoff's Law problem on this practice!!

We expand the concept of changing electric and magnetic fields and how indeed these fields produce waves of a type we never encountered in physics part one. Electromagnetic waves are energy and can travel in vacuum at the speed of light. From these laws comes the unification that the electromagnetic spectrum is much more than just visible light, but indeed covers anything from long radio waves to very short cosmic rays.