Assume all temperatures to be exact, and neglect significant figures for small changes in dimension.
When exposed to sunlight, a hole in a sheet of copper expands in diameter by 0.152% compared to its diameter at 71?F.

What is the Celsius temperature of the copper sheet in the sun?

Temp = ? ?C

A skier of mass 60 kg starts at the top of a steep slope with an incline of 40 degrees . The slope has a slight coefficient of kinetic friction of 0.05 . The slope is L = 100 meters long. At the bottom of the slope, there is an ice ramp (frictionless) that is 10 meters long and angled up at 30 degrees.

a) Draw a diagram of the problem.

b) How much potential energy does the skier start with?

c) How much total energy does the skier start with?

d) How much energy is lost to friction on the slope?

e) How fast is the skier traveling when she flies off the ramp?

f) If there is a large trampoline positioned to catch the skier at the same altitude (y-position) as the beginning of the ramp, where should it be positioned?

g) The trampoline behaves like a spring. If the first bounce on the trampoline depresses the trampoline surface by delta y=1m, Without worrying about energy losses, what is the characteristic spring constant of the trampoline?

h) Due to losses in the system, the trampoline losses about 2000 Joules every bounce. How many times does the skier bounce? Where does the 1000 Joules on each bounce go? Speculate.

A 244 g mass is hung on a spring. As a result the spring stretches 20.5 cm. If the object is then pulled an additional 3.0 cm downward and released, what is the period of the resulting oscillation?

Please show work :)

F=kx found k, then use 2pi(sqrtm/k)? convert centimeters to meters and grams to kg? I resulted T= 0.972 confirm please.

Show that the acceleration of any object down a frictionless incline that makes an angle theta with the horizontal is a= g sin theta (note that the acceleration is independent of mass.

Two 10-cm-diameter charged rings face each other, 15cm apart. The left ring is charged to -29nC and the right ring is charged to +29nC .

What is the magnitude of the electric field E?  at the midpoint between the two rings?

What is the magnitude of the force F?  on a -1.0 nC charge placed at the midpoint?

A sky diver and her parachute system weigh a total of 800 N. She is falling vertically at v = 30 m/s when her parachute opens. At the instant that the parachute opens, the drag force acting vertically upward on the open chute is equal to F = 0.5v2.

Draw a FBD of the diver-parachute.

Draw a Kinetic diagram of the diver-parachute.

At the instant that the chute opens, calculate the vertical acceleration of the

sky diver.

Why does the sky diver

A capacitor is made from two hollow, coaxial, iron cylinders, one inside the other. The inner cylinder is negatively charged and the outer is positively charged; the magnitude of the charge on each is 12.0 pC . The inner cylinder has a radius of 0.500 mm , the outer one has a radius of 7.60 mm , and the length of each cylinder is 24.0 cm .

Part A

What is the capacitance?

Use 8.854×10⁻¹² F/m for the permittivity of free space.

C=___ F

Part B

What applied potential difference is necessary to produce these charges on the cylinders?

V=___ V

an object 5 cm tall is placed 40 cm from a flat mirror find a) the distance from the object to the image, b) the height of the image, and c) the images magnification

Select True or False for the following statements about electromagnetic waves.

True False  A vertical automobile antenna is sensitive to electric fields polarized horizontally.
True False  The Earth's atmosphere is quite transparent to infrared radiation.
True False  Gamma rays can be produced through electrons oscillating in wires of electric circuits.
True False  Radio waves have wavelengths longer than 1 m.
True False  X-rays are produced by a glowing light bulb.
True False  Blue light has a longer wavelength than red.
True False  The sun's radiation is most intense in the visible region.

Near the surface of the Earth, the acceleration due to gravity is g = 9.8 m/s^2. The radius of the Earth is 6370 km. How far from the Earth's center would you have to go to reduce g to a value of 3.6 m/s^2?

1. Calculate the frequency in Hz of a typical green photon emitted by the Sun. What is the physical interpretation of this (very high) frequency? (That is, what is oscillating?)

An experiment to measure the value of g is constructed using a tall tower outfitted with two sensing devices, one a distance H above the other. A small ball is fired straight up in the tower so that it rises to near the top and then falls back down; each sensing device reads out the time that elapses between the ball going up past the sensor and back down past the sensor.

(a) It takes a time 2t₁ for the ball to rise past and then come back down past the lower sensor, and a time 2t₂ for the ball to rise past and then come back down past the upper sensor. Find an expression for g using these times and the height H. (Use the following as necessary: t₁, t₂, and H.)

(b) Determine the value of g if H equals 21 m, t₁ equals 4 s, and t₂ equals 3.42 s.

Thank you for the help- I can't figure out how to set up the first part and get an equation that will actually allow me to solve the second part. Let me know what steps you used. Thanks!

A crate rests on a frictionless incline, and is attached to a bucket of nails through a frictionless and weightless pulley as is shown.
Crate = 12.0 Kg Bucket = 25.0 Kg Angle = 20 degrees





a) You may assume that the crate accelerates up the incline. Calculate the magnitude of the acceleration of the crate. (8 points)










a = ________

b) If the acceleration of the crate was calculated to be a negative value, what could be said about the assumption in part a) that the crate moved up the incline? (2 points)






c) What is the magnitude of the Normal force of the incline pushing up on the crate (find N the Normal Force) ? (6 points)







N = _________

d) It turns out that there really is friction between the crate and the incline. The value of the friction coefficients is Us = 0.25, and Uk = 0.15. What will the acceleration be of the crate up the incline if you take in account friction? (8 points)











a = _________

e) A workman who was watching the crate accelerate up the incline decides he wants to adjust the system so that the crate maintains a steady speed while traveling up the incline. He removes nails from the bucket to achieve this goal. Taking into account the friction from part d), what should the new mass of the bucket of nails be to make this happen? (8 points)






m = ___________

A garden hose with a small puncture is stretched horizontally along the ground. The hose is attached to an open water faucet at one end and a closed nozzle at the other end. As you might suspect, water pressure builds up and water squirts vertically out of the puncture to a height of 0.73 m. Determine the pressure inside the hose. (Enter your answer to the nearest 1000 Pa.)

_____________Pa

A particle carrying a charge of 5.0 μC is located at the origin of a rectangular coordinate system, and a particle carrying a charge of 3.0 μC is located at (0, 5.0 m).

A.

What are the x and ycomponents of the magnitude of the electric field at the position (5.0 m, 0)?

Enter your answers numerically separated by a comma.

B.

What are the x and ycomponents of the magnitude of the electric field at the position (-5.0 m, 0)?

Enter your answers numerically separated by a comma.