Missed Questions 2

Question 1

If dealing with force on an electron vs proton in a magnetic field…

Answer 1

do everything for the electron with the RHR and then just switch the direction (calculate with the force exerted on electron)

Question 2

Which of the following is NOT true for every possible motion involving a constant speed?

Answer 2

the acceleration is zero. If the object is changing direction, its velocity is changing -> there is some force (/acceleration)

Question 3

Impulse equation

Answer 3

impulse (change in momentum) = deltaP = m(vF - v0)

Question 4

Induction definition

Answer 4

charging without physical contact

Question 5

If trying to find the point between two charges where the electric field is zero…(two cases)

Answer 5

if both are the same charge, the point will be in-between them. If of different charge, the point will be closer to the smaller magnitude charge, outside the pair

Question 6

Capacitance equation

Answer 6

C = Q/V

Question 7

electric potential energy of a charge, q

Answer 7

Ue = qEd, where q is the charge, E is the electric field, and d is the distance between the charge and the charged plate

Question 8

Brightness is determined by…

Answer 8

Power. P = I^2*R

Question 9

a charge entering a magnetic field, with mass m (equation to find all properties)

Answer 9

mv^2/r = qv*B

Question 10

Which of (uniform gravity field, uniform electric field, uniform magnetic field) CANNOT change the SPEED of the object that is acted upon by the field?

Answer 10

Uniform magnetic field only. A magnetic field applies a force in a direction that is perpendicular to the motion of the object. As a result, the forward speed is not changed, only the direction.

Question 11

Induced current (with flux)

Answer 11

emf = BLv, and since I = V/R, the total current induced in the loop is I = BLv/R, where R is the resistance

Question 12

Which term describes the separation of white light into separate colors in a glass prism due to small differences in the index of refraction for each wavelength?

Answer 12

Dispersion.

Question 13

As light goes from glass into air, and the angle of the light in the glass (theta1) is adjusted until total internal inflection is observed, what is the index of refraction n1 of the glass?

Answer 13

using snell’s law, n2 (air) = 1, and total internal reflection occurs when theta2 = 90 (the angle in the air), n1sintheta1 = 11 -> n1 = 1/(sinTheta1)

Question 14

Change in length, L, due to heating

Answer 14

deltaL = alphaL0deltaT, where alpha is the coefficient of linear expansion

Question 15

The slope of a photoelectric experiment graph, f vs Kmax (eV) is always:

Answer 15

planck’s constant