1.) Identical objects are located at the same distance from two spherical mirrors, A and B. The magnifications produced by the mirrors are m_A = 3.6 and m_B = 2.1. Find the ratio f_A/f_B of the focal lengths of the mirrors.

2.) A tall tree is growing across a river from you. You would like to know the distance between yourself and the tree, as well as its height, but are unable to make the measurements directly. However, by using a mirror to form an image of the tree and then measuring the image distance and the image height, you can calculate the distance to the tree as well as its height. Suppose that this mirror produces an image of the sun, and the image is located 0.8508 m from the mirror. The same mirror is then used to produce an image of the tree. The image of the tree is 0.9932 m from the mirror. (a) How far away is the tree? (b) The image height of the tree has a magnitude of 0.12 m. How tall is the tree?

Which of the following statements explains why you cannot cool down your house by holding the refrigerator open?

Select one:

a. Cold air in the cold box will flow into the kitchen but won’t cause a noticeable temperature change.

b. The refrigerator releases heat into the kitchen to keep the cold box temperature cold.

c. Cold air in the cold box will not flow into the kitchen.

d. The refrigerator removes heat from the kitchen and then replaces it during a cycle.

Hi, could you please provide a detailed explanation.. Thank you!

Q1

(i) Explain how you can use Newton’s version of Kepler’s third law to measure mass of the Sun.

(ii) Suppose a satellite is in ‘low Earth orbit’. Will that satellite remain in orbit forever, or will it eventually fall to the ground? Please explain your answer.

Q2

A small black hole with mass equal to Earth’s mass hits the Sun, and eventually settles down in the core. Briefly explain what you think would happen to the stellar structure.

A 6.35 mm high firefly sits on the axis of, and 14.1 cm in front of, the thin lens A, whose focal length is 5.03 cm. Behind lens A there is another thin lens, lens B, with a focal length of 25.7 cm. The two lenses share a common axis and are 61.5 cm apart.

Is the image of the firefly that lens B forms real or virtual?

real

virtual

How far from lens B is this image located? Express the answer as a positive number.

image distance from lens B:

cm

What is the height of this image? Express the answer as a positive number.

image height:

mm

Is this image upright or inverted with respect to the firefly?

Two 0.60 kg basketballs, each with a radius of 10 cm, are just touching. Ignore any other gravitational interactions.

(a) How much energy is required to change the separation between the centers of the basketballs to 1.0 m?
_____ J
(b) How much energy is required to change the separation between the centers of the basketballs to 10 m?
_____ J

As usual, if you don't draw the picture, label distances, you'll use the formula incorrectly.

2)A 0.520-kg object attached to a spring with a force constant of 8.00 N/m vibrates in simple harmonic motion with an amplitude of 10.2 cm. (Assume the position of the object is at the origin at t = 0.)

(a) Calculate the maximum value of its speed.
Answer must be in cm/s

(b) Calculate the maximum value of its acceleration.
Answer must be in cm/s²

(c) Calculate the value of its speed when the object is 8.20 cm from the equilibrium position.
Answer must be in cm/s

(d) Calculate the value of its acceleration when the object is 8.20 cm from the equilibrium position.
Answer must be in cm/s²

(e) Calculate the time interval required for the object to move from x = 0 to x = 2.20 cm.
Answer must be in s

5) Calculate the length of a pipe that has a fundamental frequency of 476 Hz. (Take the speed of sound in air to be 343 m/s.)

(a) Assume the pipe is closed at one end.
Answer must be in m

(b) Assume the pipe is open at both ends.

Answer must be in m

Chapter 10 [ Essential University of Physics( 3^rd ed.)]

Given the following R_disk= 2.50 cm, R_axle= 0.250 cm, M_disk= 25.0 g, M_axle= 0.750 g,  L_axle= 1.00 cm, and state any assumption used. a) Determine the rotational inertia of yo-yo about its center. (b) Derive using force and torque the expression for the linear acceleration a_cm of a yo-yo rolling down a string using an approach similar to that of the object rolling down a ramp. (c) Calculate linear acceleration of the yo-yo for the given values.

The fist (thin) string in a guitar should be two octaves higher than the sixth (thick) string, that is, its fundamental frequency is four times higher. If both strings are equal in length and under the same tension, what would the ratio of their linear mass densities be?

Physical Chemistry I

Calculate the values q, w, deltaU, and deltaH for the reversible adiabatic expansion of 1 mole of an ideal monatomic gas from 5.00m³ to 8.00m³. The temperature of the gas is initially 298K with C_v = 3/2nR.

[Q5-Home] (This question has 4 parts) You have a RC circuit connected to AC sine wave of 10 Volts peak. Your capacitor is 100 μF and your resistor is 10 Ω in series. For frequencies ranging from f=20 Hz to f=100 Hz at 20 Hz intervals and then discrete values of 200, 500, 1000 and 2000 Hz, compute and plot frequency (x-axis, logarithmic) vs. Q5a) iRMS and Q5b) VC. Use the solved problem in 2.4 as your guide Q5c) What is the impact of frequency on iRMS and VC? Q5d) Discuss the physical interpretation of these results. [Hint: For each frequency calculate XC, then the impedance (Z), then iRMS and so forth].

Mass 1 is moving at 6 m/s in the +x direction and it collides in a perfectly elastically with mass 2 of 2 kg moving at 15 in the -x direction. They collide for 0.2 seconds, and the average force on mass 1 is 149 N in the -x direction. What is the mass of mass 1 in kg?

In a physics lab, a cube slides down a friction-less incline as shown the figure below and elastically strikes another cube at the bottom that is only one-half its mass. If the incline is h = 28 cm high and the table is H = 85.1 cm off the floor, where does the larger cube land, in cm, horizontally away from the edge of table? [Hint: Both leave the incline moving horizontally.]

Bifocal glasses are used to correct both nearsightedness and farsightedness at the same time. (Figure 1)

Part A: If the near points in the right and left eyes are 38.0 cm and 46.0 cm , respectively, and the far point is 210 cm for both eyes, what are the powers of the lens prescribed for the right eye? (Assume that the glasses are worn 3.00 cm from the eyes.)

Part B: What are the powers of the lens prescribed for the left eye?

In an old-fashioned amusement park ride, passengers stand inside a 4.5-m-diameter hollow steel cylinder with their backs against the wall. The cylinder begins to rotate about a vertical axis. Then the floor on which the passengers are standing suddenly drops away! If all goes well, the passengers will "stick" to the wall and not slide. Clothing has a static coefficient of friction against steel in the range 0.65 to 1.0 and a kinetic coefficient in the range 0.40 to 0.70. A sign next to the entrance says "No children under 30 kg allowed." What is the minimum angular speed, in rpm, for which the ride is safe?