An object is attached to a spring; which is attached to a wall. Describe its motion. (max acceleration, max velocity).

A student holds a book at rest on the palm of his hand. he lifts the book straight up, bringing it to rest again at a high point.

PART A:

1. Is the net work done on the book positive negative or zero? Explain.

For this, I think the net work is zero because as he speeds the book up the work being done is positive, but the work is negative when he begins to slow down to rest again at high point.

2. is the change in the gravitational potential energy postive, negative or zero? explain.

For this, I think this is positive because the displacement of the book is upward.

3. Is the ttotal mechanical energy conserved? Explain.

For this, I feel like its not conserved... but don't know why.

***** for part A, if you have better explanation, please do tell me. also, Part A #3, Could someone explain to me why mechanical energy is not conserved?

PART B:

Consider the following discussion about the situation described above:

Darius: "when the book was lifted up, it gained potential energy but not kinetic energy. That means the change in total mechanical energy is positive."

Katrina: "Also, the net work on the book is zero, because the work you did on the book is cancelled by the work the earth did on the book."

Volibear: "Does this mean the law of conservation of energy is violated? There was zero net work on the book but its energy increased."

Question: Which of these ideas are solid and which ideas need to be revised? How would you help Darius, Katrina, Volibear make sense of the situation?

Please answer with clarity.

The wavelength of the four Balmer series lines for hydrogen are found to be 410.1, 434.3, 486.6, and 655.9 nm. What average percentage difference is found between these wavelength numbers and those predicted by 1 λ = R 1 nf2 − 1 ni2 ? It is amazing how well a simple formula (disconnected originally from theory) could duplicate this phenomenon.

A spaceship of triangular shape, having a length three times its width, is capable of relativistic speeds. How fast would it have to move so that to a stationary observer its length would equal its width?

a bullet of mass m and speed v is fired at an initially stationary sphere. The bullet goes through the sphere, and exits with a speed of v/3. The sphere is attached to a rigid pole of length L and negligible mass. What is the minimum value of v such that the sphere will barely swing through a complete vertical circle? (Use the following as necessary: m, L, g, and M for the mass of the sphere.)

What were the conditions necessary to advance astronomical knowledge from Copernicus to Newton? How did they develop during the seventeenth century?

There queer gangs of young Socialists, youths and girls (Nazis),.... They strike one as strange. something primitive, like loose roving gangs of broken, scattered tribes...as if everything and everybody recoiled from the old unison, as barbarians lurking in a wood recoil out of sight�

A box of textbooks of mass 25.0 kg rests on a loading ramp that makes an angle α with the horizontal. The coefficient of kinetic friction is 0.23 and the coefficient of static friction is 0.36.

A) As the angle α is increased, find the minimum angle at which the box starts to slip. Express your answer using two significant figures.

B) At this angle, find the acceleration once the box has begun to move. Express your answer using two significant figures.

C) At this angle, how fast will the box be moving after it has slid a distance 4.9 m along the loading ramp? Express your answer using two significant figures.

6a) The work function of a clean tungsten surface is 4.50 eV. Find the speed of the fastest electrons emitted from a tungsten surface when light of 5-eV photon energy shines on the surface.

You hike up to the top of Granite Peak in the Trinity Alps to think about physics.

1. Do you have more potential or kinetic energy at the top of the mountain than you did at the bottom? Explain.
2. Do you have more, less, or the same amount of energy at the top of the mountain than when you started? (Let’s assume you did not eat anything on the way up.) Explain.
3. How has the total energy of the Solar System changed due to your hike up the mountain? Explain.
4. If you push a rock off the top, will it end up with more, less, or the same amount of energy at the bottom? Explain.
5. For each of the following types of energy, describe whether you gained it, you lost it, or it stayed the same during your hike:
   1. Gravitational potential energy
   2. Energy stored in the atomic nuclei in your body
   3. Heat energy
   4. Chemical potential energy stored in the fat cells in your body
   5. Sound energy from your footsteps
   6. Energy given to you by a wind blowing at your back

List out at least 3 uses for an RC circuit and explain how the RC would affect the use.

3. (15 pts) Consider a second-order dynamic system composed of the classical spring, mass, and damper, with spring constant k , mass m , and damping constant c .

a) Generate expressions for the undamped natural frequency ω n and the damping ratio ζ in
terms of k , m , and c .

b) If the spring constant k is increased, but m and c are unchanged, predict whether ω n will increase, decrease, or remain the same. Justify.

c) If the spring constant k is increased, but m and c are unchanged, predict whether ζ will increase, decrease, or remain the same. Justify.

In the figure, three connected blocks are pulled to the right on a horizontal frictionless table by a force of magnitude T3 = 16.0 N. If m1 = 18.3 kg, m2 = 22.0 kg, and m3 = 35.3 kg, calculate (a) the magnitude of the system's acceleration, (b) the tension T1, and (c) the tension T2.