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?

A long, straight wire carrying a current I₁ is placed on a horizontal table in front of you and the direction of the current points +x axis. The magnetic field produced by the current I₁ at a point 5 cm above the wire is 0.2 T. A second parallel wire carrying a current I₂ = 3I₁ is placed 10 cm above the first wire and the direction of the current also points +x axis. What is the magnitude of the net magnetic field produced by these two currents at a point 5 cm above the table?

Assume a liter of milk has an activity of 1960 pCi due to ⁴⁰₁₉K, with RBE = 1. If a person drinks 2 glasses (0.440 L) per day, estimate the total dose received in a year. As a crude model, assume the milk stays in the stomach 13.4 h and is then released. Assume also that 15.0 percent of the 1.50 MeV released per decay is absorbed by the body, and that this person is a 64.6 kg adult.

? The maximum annual dose to be used for this calculation is given below. ?

b)
What percentage of the allowed dose does this correspond to if the allowed yearly dose is 5 mSv?

A parallel-plate capacitor with circular plates of radius a separated by a distance d is being charged though a resistor R and battery with emf E.

1 (a) (5pts.) Make a diagram showing the direction of the induced magnetic field between the plates.

(b) (15pts) Show that the magnitude of this induced magnetic field r < a is given by B(r) = µ0 r 2π a2 E R e −t/RC, where r is the distance to the axis of symmetry of the plates.

(c) (4pts.) Why is the magnetic field independent on the distance to either of the plates?

(d) (6pts.) What is the maximum magnetic field between the plates if they have a radius of a = 1.0 cm, and the capacitor is being charged by a 120.0 V battery through a 5.0 Ω resistor?

What phase difference between two otherwise identical traveling waves, moving in the same direction along a stretched string, will result in the combined wave having an amplitude 1.3 times that of the common amplitude of the two combining waves? Express your answer in (a) degrees, (b) radians, and (c) as a fraction of the wavelength.

A set of jumper cables used to start a car from another car's battery is connected to the terminals of both batteries.  

If 20 A of current exists in the cables during the starting procedure and the cables are parallel and 20 cm apart, do the wires repel or attract?

If 20  of current exists in the cables during the starting procedure and the cables are parallel and 20  apart, do the wires repel or attract?

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Part B

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Part C

What is the magnetic field strength that each wire produces at the location of the other?

Express your answer using two significant figures.

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Part D

What is the force per unit length on the cables?

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A helicopter propeller blade starts from rest and experiences a constant angular acceleration of 14.0 rad/s2. Find the speed of a point on the blade 5.60 m from the axis of rotation when the blade has completed 13 revolutions.

A uniform ladder 5.30  m long rests against a frictionless, vertical wall with its lower end 3.10  m from the wall. The ladder weighs 157  N . The coefficient of static friction between the foot of the ladder and the ground is 0.430. A painter weighing 739  N climbs slowly up the ladder.

How far along the ladder can the painter climb before the ladder starts to slip?