A cubical box, open at the top, with edge length 81.0 cm, is constructed from metal plate of uniform density and negligible thickness. One of the bottom corners of the box is at 0,0,0, the base of the box is in the x-y plane and the box is the positive quadrant. What is the x coordinate of the center of mass of the box (in cm.)?

What is the y coordinate of the center of mass of the box (in cm.)?

What is the z coordinate of the center of mass of the box (in cm.)?

While driving on a highway on a hot day, have you ever  seen what appears to be a

In the television show “The Six Million Dollar Man”, Colonel Austin had superhuman powers. In one episode, he tries to catch a man fleeing in a sports car. We’ll assume in this problem that the distance between them at t=0 is 100 m. The car starts at rest. At t = 0.0 s, the driver notices Colonel Austin. From then on, the car accelerates at 5.0 m s -2 , away from Austin. Sweet, but a bit slow on the uptake, Colonel Austin remains motionless until t = 2.0 s, at which point he begins his pursuit, at a constant speed of 50 m/s. a) How far ahead is the car when Colonel Austin begins to move? b) At what time (t>0) is Austin furthest ahead of the car? And what is that separation? c) At what time(s) does Austin catch the car? d) What is the critical initial separation (all other parameters remaining the same) beyond which Colonel Austin will never catch the car?

What are the dangers of nuclear radiation? Is radiation less dangerous than we think? More dangerous? What radiation dangers do you think are worth worrying about, and what are not? What facts and examples support your conclusions?

The 2011 meltdown of 3 reactors at the Fukushima Daiichi nuclear power plant is in the news again this week as the criminal trial against the plant executives comes to a close. How deadly was the Fukushima disaster? (And how does this compare to the deadliness of the earthquake and tsunami that caused it?) Have you heard of Masao Yoshida, and why people consider him the hero of Fukushima?

1. A force of 45.6 N is applied to a 2.00 kg disc. What is the disk acceleration? 5 points

2. Find the force that causes an acceleration of 6.4 m/s2 to a mass object of 0.50 kg. 5 points

3. A force of 5.34 N acts for 4.23 seconds on a mass that is initially at rest and causes it to move at a distance of 4.75 meters in a straight line. Determine the mass. 10 points

1) A spring is 17.8 cm long when it is lying on a table. One end is then attached to a hook and the other end is pulled by a force that increases to 28.0 N , causing the spring to stretch to a length of 19.7 cm

a)What is the force constant of this spring?

b)How much work was required to stretch the spring from 17.8 cm to 19.7 cm ?

c)How long will the spring be if the 28.0 N force is replaced by a 56.0 N force?

2)Two tugboats pull a disabled supertanker. Each tug exerts a constant force of 1.95×10⁶ N , one 15 ∘west of north and the other 15 ∘ east of north, as they pull the tanker 0.84 km toward the north.

-What is the total work they do on the supertanker?

Express your answer with the appropriate units.

3)A bullet is fired into a large stationary absorber and comes to rest. Temperature measurements of the absorber show that the bullet lost 2150 J of kinetic energy, and high-speed photos of the bullet show that it was moving at 980 m/s just as it struck the absorber.

-What is the mass of the bullet?

4)A running house cat has 13.5 J of kinetic energy at speed v.

a)At what speed (in terms of v) will she have 27.0 J of kinetic energy?

Express your answer in terms of v.

b)What would her kinetic energy be if she ran half as fast as the speed in part A?

5)About 50000 years ago, a meteor crashed into the earth near present-day Flagstaff, Arizona. Recent (2005) measurements estimate that this meteor had a mass of about 1.4×108kg (around 150000 tons) and hit the ground at 12 km/s.

a)How much kinetic energy did this meteor deliver to the ground?

Express your answer using two significant figures.

b)How does this energy compare to the energy produced in one day by a standard coal-fired power plant, which generates about 1 billion joules per second?

Express your answer using one significant figure.

6)The food calorie, equal to 4186 J, is a measure of how much energy is released when food is metabolized by the body. A certain brand of fruit-and-cereal bar contains 160 food calories per bar.

a)If a 60.0 kg hiker eats one of these bars, how high a mountain must he climb to "work off" the calories, assuming that all the food energy goes only into increasing gravitational potential energy?

b)If, as is typical, only 23.0 % of the food calories go into mechanical energy, what would be the answer to part (a)? (Note: In this and all other problems, we are assuming that 100 % of the food calories that are eaten are absorbed and used by the body. This is actually not true. A person's "metabolic efficiency" is the percentage of calories eaten that are actually used; the rest are eliminated by the body. Metabolic efficiency varies considerably from person to person.)

7)Tendons are strong elastic fibers that attach muscles to bones. To a reasonable approximation, they obey Hooke's law. In laboratory tests on a particular tendon, it was found that, when a 252 gobject was hung from it, the tendon stretched 1.20 cm .

a)Find the force constant of this tendon in N/m.

b)Because of its thickness, the maximum tension this tendon can support without rupturing is 137 N . By how much can the tendon stretch without rupturing, and how much energy is stored in it at that point?

8)Pebbles of weight w are launched from the edge of a vertical cliff of height h at speed v0. How fast (in terms of the quantities just given) will these pebbles be moving when they reach the ground if they are launched

a)straight up.

b)straight down.

c)horizontally away from the cliff.

d)at an angle θ above the horizontal.

e)How would the answers to the previous parts change if the pebbles weighed twice as much?

9)A 13.0 N package of whole wheat flour is suddenly placed on the pan of a scale such as you find in grocery stores. The pan is supported from below by a vertical spring of force constant 315 N/m .0

-If the pan has negligible weight, find the maximum distance the spring will be compressed if no energy is dissipated by friction.

10)A 15.0 g plastic ball is dropped from a height of 2.90 m and is moving at 2.70 m/s just before it hits the floor.

-How much mechanical energy was lost during the ball's fall?

For your final exam in electronics, you're asked to build an LC circuit that oscillates at 15kHz . In addition, the maximum current must be 0.15A and the maximum energy stored in the capacitor must be 1.0

Discussion Question 1: Discuss the differences between the Einstein’s Theory of Relativity and Classical Physics Theory (i.e. Galileo and Newton, etc.)

Discussion Question 2: Discuss the wave-particle duality of light and its implications. What are possible industrial applications?

Five different experiments are carried out. In each experiment, a block is attached to a horizontal spring. The block is pulled back a certain distance and released. The block oscillates back and forth on a frictionless surface. Rank the amplitude of oscillation for each of the following situations. (Rank the smallest amplitude as 1).
1) A block of mass M is attached to a spring with a spring constant k, pulled back a distance 2d, and released.
2) A block of mass M is attached to a spring with a spring constant 2k, pulled back a distance (1/2)d, and released.
3) A block of mass (1/2)M is attached to a spring with a spring constant k, pulled back a distance d, and released.
4) A block of mass M is attached to a spring with a spring constant 2k, pulled back a distance d, and released.
5) A block of mass M is attached to a spring with a spring constant k, pulled back a distance d, and released.

1.A cylinder of radius a = 7 cm and height h = 11.6 cm is aligned with its axis along the y-axis as shown. What is the total flux ? that passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

2.Another infinite line of charge with charge density ?2 = -14.7 ?C/cm parallel to the y-axis is now added at x = 3.5 cm as shown.

3.What is the new value for Ex(P), the x-component of the electric field at point P?

4.What is the total flux ? that now passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

5. The initial infinite line of charge is now moved so that it is parallel to the y-axis at x = -3.5cm.What is the new value for Ex(P), the x-component of the electric field at point P?

6. What is the total flux ? that now passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

The absorption spectrum of an atom consists of the wavelengths 200 nm, 300nm, and 500 nm.

a) Draw the atom's energy-level diagram.

b) What wavelengths are seen in the atom's emission spectrum?

(Please show all the steps and calculations with simple explanation. Thank you)

An object of mass 0.50 kg is released from the top of a building of height 6 m. The object experiences a horizontal constant force of 1.2 N due to a wind blowing parallel to the face of the building.

(a) Find the time it takes for the object to strike the ground. s

(b) What is the magnitude of the acceleration of the object? m/s2

c) Through what horizontal distance does the object move before it hits the ground?

A laser beam of wavelength 580nm is incident normally on a transmission grating having 440lines/mm .

Find the angles of deviation in the first, second, and third orders of bright spots.

Two objects with masses 4.20kg and 2.20kg hang 0.500m above the floor from the ends of a cord 7.30m long passing over a frictionless pulley. Both objects start from rest.

a) Find the maximum height reached by the 2.20kg object.

How to to find wave speed of a string using derivation of second newton law ?