Other Physics Answers

Assuming your exam answer booklet for this course in the end of

semester exams is flagged (indicated) by your antivirus as being infected

with a virus but you have just about 5 hours to submit/upload your

answer booklet to lemsas.net. Discuss what you would do to avoid not

submitting your answer booklet and thereby not failing the course.

A solid conducting sphere of radius 30 cm has a charge of 4 uC. If the potential is zero at infinity. Find the value of the potential at the following distances from the center of the sphere: a) 45 cm b) 30 cm c) 15 cm

A crazy physics teacher has a golden spear of 3.2m. How long it will be when he heats it up to 1000C from room temperature(+20C)?

Single choice.

The frequency of a car horn is 400 Hz. Find (a) the wavelength of the sound, and (b) the frequency observed if the car moves with a speed us = 34.0 m/s through still air toward a stationary receiver. Take the speed of sound in air to be 340 m/s. (c) Find the frequency observed if the car is stationary and a receiver moves with a speed us= 34.0 m/s toward the car.

The tension in a string is provided by hanging an object of mass m=3.00 kg at one end as shown in the figure below. The length of the string is L=2.50 m and its mass is ms= 50.0 g. What is the speed of waves in m/s on the string?

A 2.00-kg object is attached to a spring. The force constant of the spring is k=196 N/m. The object is held a distance 5.00 cm from the equilibrium position and is released at t 0. (a) Find the angular frequency ω, (b) the frequency f, (c) the period T and (d) write x (in cm) as a function (cosine) of time.

Show your solutions:

A light beam makes an angle of 60 degrees to the normal as it strikes a transparent substance. Part of the beam is reflected from the surface into the air (n = 1) and part is refracted through the substance. The reflected and the refracted beams make an angle of 90 degrees with each other.

  a. Calculate the index of refraction of the substance.

  b. Calculate the critical angle for light leaving the substance and going into a material with an index of refraction of 1.30

Show your solutions:

The speed of light in a certain material is 2 x 10⁸ m/s. The speed of light in a vacuum is 3 x 10⁸ m/s. Calculate the index of refraction of the material.

Show your solution:

A beam of light enters water from air. The angle between the beam and the surface of the water is 60 degrees. The index of refraction of water is 1.33.

            a. What is the angle of reflection?

            b. What is the angle of refraction?

Show your solution in each question below:

1) The speed of an ocean wave on the coast is 42 m/s; the wavelength is 1.5 m. What is the frequency with which the wave hits the beach?

2) Radio waves travel at the speed of light, 3 x 10⁸ m/s. What is the wavelength of a radio wave from an AM station broadcasting at a frequency of 750 Hz? Find the wavelength in meter and kilometer.

3) A standing wave in a clothesline has 3 loops. . The clothesline is 12 m long and is vibrating at 0.5 vibrations per second. What is the speed of the wave?