Suppose you’re eating in yet another restaurant where the dishes are shared at the table and all placed uniformly on a rotating disk-like surface. Model this surface as a thin disk of radius 45.3 cm. Someone else has spun the surface, such that it is initially at an angular speed of 0.4 rev/s. The surface and food has a combined mass of 3.3 kg. The waiter, to show off, throws a new dish of dumplings (mass 0.8 kg) onto the surface at a speed of 0.5 m/s, such that the dish lands on and sticks to the very edge of the surface moving in the same direction as the rotating food. While this is happening, you quickly calculate the final angular speed of the food so that you can predict its location at any time before others have a chance to eat the dumplings. What is this speed, in rad/s?

A container has a flat bottom made of aluminum that is 1.18 -cm thick. The walls are insulated with thick styrofoam. The exterior bottom of the container is in continual contact with boiling water. Inside the container, ethanol (ethyl alcohol) is boiling. How long until the alcohol completely boils away if initially it has a depth of 5 cm? Assume that the thermal conductivity of aluminum is 220 W/m· ◦C, the latent heat of vaporization of ethanol is 854 kJ/kg, the boiling point of ethanol is 78.2 ◦C, and the density of ethanol is 785 kg/m3 . [50, 80 s]

A proton is fired from far away toward the nucleus of a mercury atom. Mercury is element number 80, and the diameter of the nucleus is 14.0 fm.

If the proton is fired at a speed of 4.4

A bicycle racer sprints at the end of a race to clinch a victory. The racer has an initial velocity of 13.0 m/s and accelerates at the rate of 0.450 m/s^2 for 7.00 s.

(a) What is his final velocity (in m/s)? 16.15 m/s

(b) The racer continues at this velocity to the finish line. If he was 300 m from the finish line when he started to accelerate, how much time (in s) did he save?

(c) One other racer was 5.00 m ahead when the winner started to accelerate, but he was unable to accelerate and traveled at 13.2 m/s until the finish line. How far ahead of him (in meters and in seconds) did the winner finish?

distance m?

time s?

A spacecraft starts from rest, and makes a journey to a destination 134000 km from its starting point. It does so by accelerating at a constant rate of 8.91 m/s^2 up to the midpoint of the journey, and then decelerates at the same constant rate of 8.91 m/s^2 for the second half of the journey, ending at rest. How long did the entire journey take?

A car drives around a circular track of diameter 75 m at a constant speed of 36.0 m/s. During the time it takes the car to travel 232 degrees around, what is the magnitude of the car s average acceleration?

An electron is at the origin. (a) Calculate the electric potential V_Aat point A, x= 0.250 cm. (b) Calculate the electric potential V_Bat point B, x= 0.750 cm. What is the potential difference V_B- V_A? (c) Would a negatively charged particle placed at point Anecessarily go through this same potential difference upon reaching point B? Explain.

A sphere of radius 2.09 cm and a spherical shell of radius 6.97 cm are rolling without slipping along the same floor. The two objects have the same mass. If they are to have the same total kinetic energy, what should the ratio of the sphere\'s angular speed to the spherical shell\'s angular speed be? Please provide a clear explanation. I have tried to look this problem u, but I was unable to understand exactly how the solution was found.

A person pushes a 10.5-kg shopping cart at a constant velocity for a distance of 37.6 m on a flat horizontal surface. She pushes in a direction 20.2 ° below the horizontal. A 53.1-N frictional force opposes the motion of the cart. (a) What is the magnitude of the force that the shopper exerts? Determine the work done by (b) the pushing force, (c) the frictional force, and (d) the gravitational force.

Is there a material which can allow light (or any other EM radiation) to pass through from one side as if it is transparent but its other side reflects light like a mirror?

a glass tube both ends are open is dipped inside mercury so that one half is above the mercury level. then the one half of open end is closed and taken out there with a

10 cm long mercury left. if atmospheric pressure is 76cnHG calculate the length of the tube

answer is 16 cm pls explain the answer

When jumping straight down, you can be seriously injured if you land stiff-legged. One way to avoid injury is to bend your knees upon landing to reduce the force of the impact. A 67.3-kg man just before contact with the ground has a speed of 3.81 m/s. (a) In a stiff-legged landing he comes to a halt in 2.92 ms. Find the magnitude of the average net force that acts on him during this time. (b) When he bends his knees, he comes to a halt in 0.255 s. Find the magnitude of the average net force now. (c) During the landing, the force of the ground on the man points upward, while the force due to gravity points downward. The average net force acting on the man includes both of these forces. Taking into account the directions of the forces, find the magnitude of the force applied by the ground on the man in part (b).

Enter numerical answers with THREE SIGNIFICANT FIGURES.

A soap bubble of uniform thickness has an index of refraction of 1.53, and is illuminated by light with a wavelength of 580. nm.

a) Calculate the wavelength of the light in the soap bubble. (Enter THREE sig figs)
nm


Which two rays will interfere with each other?


How many ½ λ shifts must be considered, and where do these shifts (if any) occur? Briefly explain your answer.



c) What is the minimum thickness of a soap bubble such that the light is strongly reflected? (Enter THREE sig figs)
nm

Question 10

The statements in the following list all refer to Quantum Physics. Check the boxes of the THREE CORRECT statements.

1. In the photoelectric effect, the maximum energy of the emitted electrons depends on the frequency of the incoming electromagnetic radiation and not on the intensity. There is a threshold frequency below which no electrons are emitted.

2. Electrons can behave both as particles and as waves.

3. It is not necessary to know the potential energy function of a particle in order to to solve the time-independent Schrödinger equation and obtain the wave function describing it.

4. The allowed energy levels of a particle in an infinite square well are equally spaced.

5. In spectroscopic notation, the letters 's', 'p', 'd', etc. are used to identify the magnetic quantum number m_l associated to a state or energy level.

6. An atom can be stimulated to make a transition from a higher to a lower energy level by a photon of the appropriate energy.

1. Parallel light rays pass through a converging lens and

a. stay parallel

b. all travel to a point that is at a defined distance away from the lens

c. diverge rapidly

d. reflect back to a point in front of the lens

2. For a lens with a given focal length of 10 cm and an object placed 15 cm in front of it, where is the image located?

a. 30 cm

b. 10 cm c. 20 cm

d. 25 cm

3. For problem number 2, what is the magnification?

a. M = 1/2

b. M = -1/2

c. M = 2

d. M = -2

4. For problem number 2, describe the relation of the image height to the object height. Is the

a. image height smaller than the object height

b. image height larger than the object height

c. image height and object height are equal

5. Describe the image that is formed in problem #2. Is it?

a. real and upright

b. real and virtual

c. real and inverted

d. virtual and inverted

6. For a lens with a given focal length of 10 cm and an object placed 5 cm in front of it, where is the image located?

a. 10 cm behind the lens

b. 10 cm in front of the lens

c. 2 cm in front of the lens

d. 2 cm behind the lens

7. For problem number 6, what is the magnification?

a. M = ½

b. M = -1/2

c. M = 2

d. M = -2

8. The letter “B” in the above diagram of a camera is identified as the

a. film

b. shutter

c. lens

d. aperture

9. The letter “D” in the above diagram of a camera is identified as the

a. film

b. shutter

c. lens

d. aperture

10. To create a virtual magnified image of an object,

a) the object must be at the focal point of a concave lens.

b) the object must be just outside the focal point of a convex lens.

c) the object must be very far from a convex lens.

d) the object must be within the focal point of a convex lens.