Working with electric forces, field and potentials.

Two positive charges, charge q0 are fixed on the x axis at positions +a and -a. a) What is the Electric Field anywhere in the (x,y) plane, at position (x,y)? Be sure your answer clearly denotes the vector nature of the electric field. b) What is the electric potential at position (x,y)? c) A third charge, q3 , (mass m3 ) is at position (0, 0 y ). What is the force on this charge? d) What is the minimum speed of the third particle at position (0, 0 y ) in order for it to (i) reach the origin , (0,0) (ii) move off to infinity (plus or minus). Be sure to consider both signs of 3 q to answer these. The answers may not algebraically reduce to 'nice' solutions in general. Be sure... click for more

Electric and potential fields...(solid conducting core)

Consider a concentric spherical system made up of the following parts: A solid conducting core radius a with total charge Qc , surrounded by a conducting shell of inner radius b and outer radius c. The shell has total charge -Qc . For each of the appropriate regions, find Qenclosed , E and V. Make the appropriate set of graphs for charge density, charge enclosed, electric field, and potential as a function of radius. Use infinity as the potential reference point (V(inf)=0). Be sure to note the direction associated with vector quantities.

light

1.) A woman 1.8m tall, standing 1.24 meters from a 1m high vertical mirror can see her entire image in it. Her eyes are 144 mm below the very top of her head. How high above the floor is the bottom edge of the mirror? 2.) A beam of light impinges on the top surface of a 7.30 cm thick parallel glass (n=1.5) plate at an angle of 28.6 degrees. How long is the actual path through the glass? 3.) A 19.5 m tall building is 22.4 m behind a person who is looking directly at the middle of a mirror a distance of 2.51 m in front of him. How tall should the mirror be if the image of the building is to completely fill it top to bottom?

Understanding resistivities of paper and wood.

What is the resistivity of paper? What is the resistivity of wood?

Calculating the total energy of photons from a helium-neon laser.

A helium-neon laser gives off red light with a wavelength of 632.8 nm (nanometers). What is the energy of the photons coming out of the laser? (Hint: the speed of light is 3x10 [to the 8th pwr.] m/sec.) SIDE NOTES: We have been using very basic equations in this class, it is not advanced or anything. I do not know which equation(s) to use first of all or how to work it out. I need to show ALL work including formulas and steps, possibly drawings to. Thanks in advance!