33. Geometric Optics

A small light source is casting your shadow on a large wall. Both you and the light are on a line normal to the wall. You are one-fourth of the way from the light to the wall. How wide is your shadow compared to your normal width?

When light reflects off of a smooth surface, and rays that were initially parallel remain parallel, this is called…

It is proposed to store 1.00 kW•h = 3.60 * 10^6 J of electrical energy in a uniform magnetic field with magnitude 0.600 T. (b) If instead this amount of energy is to be stored in a volume (in vacuum) equivalent to a cube 40.0 cm on a side, what magnetic field is required?

It has been proposed to use large inductors as energy storage devices. (b) If the amount of energy calculated in part (a) is stored in an inductor in which the current is 80.0 A, what is the inductance?

It has been proposed to use large inductors as energy storage devices. (a) How much electrical energy is converted to light and thermal energy by a 150-W light bulb in one day?

A solenoid 25.0 cm long and with a cross-sectional area of 0.500 cm^2 contains 400 turns of wire and carries a current of 80.0 A. Calculate: (c) the total energy contained in the coil's magnetic field (assume the field is uniform);

How much energy is stored in a 3.0-cm-diameter, 12-cm-long solenoid that has 200 turns of wire and carries a current of 0.80 A?