Questions from College Physics

Q: A useful measure of the quality of a fiber-optic cable

A useful measure of the quality of a fiber-optic cable such as those used in endoscopes and other medical equipment is the numerical aperture. The larger the numerical aperture, the more light will be...

Q: (a) Using the result of Problem 26, calculate the

(a) Using the result of Problem 26, calculate the numerical aperture of a fiber-optic cable whose cladding and core have indices of refraction 1.40 and 1.62, respectively. (b) Light enters the fiber...

Q: The radioactive decay of 238U produces alpha particles with a kinetic energy

The radioactive decay of 238U produces alpha particles with a kinetic energy of 4.17 MeV. (a) At what speed do these alpha particles move? (b) Put yourself in the place of Rutherford and Geiger. You...

Q: Compare the orbital radii of the He+ and H atoms for

Compare the orbital radii of the He+ and H atoms for levels of equal energy (not the same value of n). Can you draw a general conclusion from your results?

Q: A motor scooter travels east at a speed of 12 m/

A motor scooter travels east at a speed of 12 m/s. The driver then reverses direction and heads west at 15 m/s. What is the change in velocity of the scooter? Give magnitude and direction.

Q: The intensity of sunlight that reaches Earth's atmosphere is 1400 W/

The intensity of sunlight that reaches Earth's atmosphere is 1400 W/m2. What is the intensity of the sunlight that reaches Jupiter? Jupiter is 5.2 times as far from the Sun as Earth. [Hint: Treat the...

Q: Sketch the shape of the string at t = 2.2

Sketch the shape of the string at t = 2.2 s.

Q: Light rays from the Sun, which is at an angle of

Light rays from the Sun, which is at an angle of 35° above the western horizon, strike the still surface of a pond. (a) What is the angle of incidence of the Sun's rays on the pond? (b) What is the...

Q: Sketch the shape of the string at t = 1.6

Sketch the shape of the string at t = 1.6 s.

Q: (a) Find the potential at points a and b in

(a) Find the potential at points a and b in the following diagram for charges Q1 = +2.50 nC and Q2 = −2.50 nC. (b) How much work must be done by an external agent to bring a point c...