A vertical infinite wire along the z-axis has two symmetries: One is a rotational symmetry around the z-axis while the other is a translational symmetry along the z-axis. Describe the symmetries of a) a sphere, b) an infinite plane, c) a circular plate, d) a finite length rod with circular cross section, and e) a finite length bar with a square cross section.

Please explain process.

The mass of the sun is 2*1030 kg. It currently consists to about 70% (mass) of hydrogen. The dominant source of energy for the sun is the pp-chain (type I) fusion process in which four protons fuse into a 4He core consisting of two protons and two neutrons. This process releases 26.22 MeV ( = 4.2*10-12 J) of energy. Assume that to first order the luminosity of the sun remains constant at 1.1 times its current-day value. How long will it take for the sun until the fraction of hydrogen is reduced from 70% to 30%?

a- Consider an electron that moves freely in metal and a particle moves freely in vacuum. Briefly explain differences between the energy of these particles. b- Briefly explain the temperature dependent conductivity of metal, semiconductor and insulator. (Please write your answer by asking your self “How and Why change” questions )

3. An inductor/resistor circuit is powered by a direct current EMF of 3.00 V until the inductor is fully powered. The decay coefficient of the circuit is 2.15 ms. The inductor has a value of 140 mH.

a) After the EMF is turned off, how long does it take the current in the circuit to drop from a max of 46.2 mA to 11.5 mA?

b) What is the value of the resistor?

c) If the inductor has a length of 0.75 cm and 3000 loops, what is its cross sectional area?

A vertical glass tube of length L = 1.280000 m is half filled with a liquid at 20.000 000 degrees C. How much will the height of the liquid column change when the tube and liquid are heated to 30.000000 degrees C? Use coefficients alpha_glass = 1.000 000 x 10^-5/K and Beta_liquid = 4.000 000 x 10^-5/K

A glass rod is rubbed on a silk cloth, and then separated
from each other. When the rod and the silk cloth are
separated by 35 cm, a force of magnitude 2.20x10^−21 N is
measured between the rod and cloth.
a) Calculate the total charge on the glass rod.
b) Calculate the total charge on the silk cloth.
c) How many electrons were transferred from the glass rod to the silk cloth.
d) Explain why a material like copper is a good conductor of electricity, while a material like wood is a poor
conductor of electricity.

One particle has a mass of 3.84 x 10-3 kg and a charge of +8.90 μC. A second particle has a mass of 8.33 x 10-3 kg and the same charge. The two particles are initially held in place and then released. The particles fly apart, and when the separation between them is 0.158 m, the speed of the 3.84 x 10-3 kg-particle is 190 m/s. Find the initial separation between the particles.

A block of mass m = 3.50 kg is released from rest from point A and slides on the frictionless track shown in the figure below. (Let h_a = 5.20 m.)

(a) Determine the block's speed at points B and C

(b) Determine the net work done by the gravitational force on the block as it moves from point A to point C.
J

A red ball is thrown down with an initial speed of 1.4 m/s from a height of 29 meters above the ground. Then, 0.6 seconds after the red ball is thrown, a blue ball is thrown upward with an initial speed of 25.6 m/s, from a height of 1 meters above the ground. The force of gravity due to the earth results in the balls each having a constant downward acceleration of 9.81 m/s².

1)

What is the speed of the red ball right before it hits the ground?

m/s

2)

How long does it take the red ball to reach the ground?

s

3)

What is the maximum height the blue ball reaches?

m

4)

What is the height of the blue ball 1.8 seconds after the red ball is thrown?

m

5)

How long after the red ball is thrown are the two balls in the air at the same height?

s

A particle moves in the xy plane with constant acceleration. At t = 0 the particle is at vector r1 = (3.6 m)i + (2.8 m)j, with velocity vector v1. At t = 3 s, the particle has moved to vector r2 = (11 m)i − (1.8 m)j and its velocity has changed to vector v2 = (4.6 m/s)i − (6.7 m/s)j. (a) Find vector v1. vector v1 = m/s

(b) What is the acceleration of the particle? vector a = m/s2

(c) What is the velocity of the particle as a function of time? vector v(t) = m/s

(d) What is the position vector of the particle as a function of time? vector r(t) = m

n = 4.43 mol of Hydrogen gas is initially at T = 336.0 K temperature and pi = 2.45×105 Pa pressure. The gas is then reversibly and isothermally compressed until its pressure reaches pf = 8.84×105 Pa. How much work did the external force perform? How much heat did the gas emit? How much entropy did the gas emit? What would be the temperature of the gas, if the gas was allowed to adiabatically expand back to its original pressure?

Suppose a friend is completing another physics assignment in their chair at their desk and you take the opportunity to turn this scenario into the physics question you now must complete. Your friend and chair have a combined constant moment of inertia of 4.6 kg m2, and the chair can freely rotate. Now your friend picks up two solid bricks (each of mass 1.4 kg) they accidentally collected from one of the campus buildings, and experiment with rotational kinematics. Supposing they hold the masses in each hand, arms outstretched, at distance of 0.7 m from their axis of rotation, and have an initial angular speed of 2.7 rev/s.

a) Calculate the distance in m of each brick from your friend’s axis of rotation if they pull the bricks inward such that their rotational speed has increased to 3.2 rev/s.

Answer: 0.396

b) What is the initial rotational kinetic energy of the system?

Answer: 21.76794

c) What is the final rotational kinetic energy of the system?

Answer: 25.79904

Could you please write down the full solution?

Two bars of equal proper length Lo approach each other, moving in a longitudinal direction parallel to a common axis with the same speed v with respect to a reference system of laboratory. What is the length of each of the bars in the reference system? linked with the other bar?

For 2 MeV alpha, beta, and gamma emissions calculate the following quantities relativistically for each emission: T (Kinetic Energy), E (total energy), gamma (correction factor), p (momentum), m (mass), and v (frequency). Use nuclear units, i.e., keV or MeV for energies, keV/c or MeV/c for momenta, MeV/c2 for masses and express velocities in units of c.

1) A car accelerates at 4 m /s / s. Assuming the car starts from rest, how far will it travel in 10 s?

2) An object falls freely from rest on a planet where the acceleration due to gravity is twice that of in Earth. Find the speed of the object after 5 second?

3) It takes 8 seconds for a stone to fall to the bottom of a mine shaft. How deep is the shaft?

4) A bag of groceries has a mass of 30 kilograms and in earth. Find its weight in the earth in moon?

5) If two force vector 20N and 40N are perpendicular to each other. Find the resultant vector?