Which of the following statements are true? Choose all that apply.

1.The length of a microscope is greater than the sum of the focal lengths of the eyepiece & objective.

2.The purpose of a large primary mirror in a telescope is to have a large magnification.

3.Better resolution is achieved with larger wavelengths.

4. Far-sighted people use converging lenses to correct their vision.

5. Nearsighted people see close up objects in focus.

6. For a telescope, the smaller f_e is, the greater the magnification.

Write 250 words.

Question: Theory -- Here, provide the relevant theoretical background including all formulas needed for the analysis. Make sure you define the different quantities and symbols that you have used in your report.

lab:

http://phys205r1.athabascau.ca/lab-manual/phys205-lab-exp4.html

Interstellar cloud having a diameter of 10¹³ km and a rotation period of 10⁶ years collaps- ing to a sphere the size of the Sun (1.4 x 10⁶ km in diameter). We point out that if all the cloud’s angular momentum went into that sphere, the sphere would have a rotation period of only 0.6 second. Do the calculation to confirm this result.

A 200 g insulated aluminum cup at 16 ∘C is filled with 255 g of water at 100 ∘C

a) Determine the final temperature of the mixture.

b)  Determine the total change in entropy as a result of the mixing process (use ΔS=∫dQ/T).

A pendulum 2.10 m long is released (from rest) at an angle θ0=30.0∘.

B. Determine the speed of the 50.0 g bob at θ=15.0∘.

C.Determine the speed of the 50.0 g bob at θ=−15.0∘ (i.e., on the opposite side).

D.Determine the tension in the cord at the lowest point (θ=0).

E. Determine the tension in the cord at the θ=15∘.

F. Determine the tension in the cord at θ=−15.0∘.

You have been called to testify as an expert witness in a trial involving a head-on collision. Car A weighs 1515 lb and was traveling eastward. Car B weighs 1125 lb and was traveling westward at 41.0 mph. The cars locked bumpers and slid eastward with their wheels locked for 18.5 ft before stopping. You have measured the coefficient of kinetic friction between the tires and the pavement to be 0.750 . How fast (in miles per hour) was car A traveling just before the collision? (This problem uses English units because they would be used in a U.S. legal proceeding.)

1. An infinitely long solenoid of radius R carries n turns per unit length and current I and is oriented such that its axis is along the z direction. What direction must a particle of charge q be moving such that it feels zero force (a) inside the solenoid (b) outside the solenoid

2. Find the maximum magnetic flux through a circular coil of radius L such that L < R placed inside the solenoid of the previous problem.

On his way to class, a student on a skateboard is accelerating on a downhill stretch. Which of the following are true.

I know the answer is

a) the skateboarder is moving in the direction of the net force

b) the skateboarder is subjected to a net external force in the direction of motion

c) the skateboarders acceleration is in the direction of the net force

I am struggling to understand why all three of these answers are correct. Could you possibly explain to me why each of these is correct. I know it is in correlation with Newtons first law but i need further explanation to help understand it because it is not clicking in my head.

Thank you for your time!!

I already finish the argumentative topic about abortion, but my professor does not want me to write about it.

Can someone help me write 500 words about this argumentation "Education should be free for everyone".

A cart changes its speed from rest to 100 m/s in 1 s. During this interval its acceleration is

1. A mechanical system with one degree of freedom oscillates about a stable equilibrium state. Its displacement from the equilibrium, x(t), satisfies the simple harmonics oscillator equation:

d2x + ω2 x = 0.dt2

(a) What is the characteristic period of the oscillation?
(b) Write a solution to the above equation for which x(0) = x0 and ẋ(0) = v0. (c) Demonstrate that E = ẋ 2 + ω 2 x 2 does not vary in time. What is the physical significance of E?

2. An damped mechanical system with one degree of freedom oscillates about a stable equilibrium state. Its displacement from the equilibrium, x(t), satisfies the damped harmonic oscillator equation:

ẍ+νẋ+ω2 x=0, where ν > 0.

(a) Demonstrate that

x = A sin(ω1 t)eγt

is a particular solution of the damped harmonic oscillator equation, and determine the values of ω1 and γ (assuming that ν < 2 ω).

(b) Demonstrate that

dE ≤ 0,dt

where E is defined in Q1(c). What is the physical significance of this equation?

3. Consider a mass-spring system consisting of two identical masses, of mass m, which slid over a frictionless horizontal surface. In order, from the left to the right, the system consists of a spring of spring constant k′ whose left end is attached to an immovable wall and whose right end is attached to the first mass, a spring of spring constant k whose left end is attached to the first mass and whose right end is attached to the second mass, and a spring of spring constant k′ whose left end is attached to the second mass and whose right end is attached to an immovable wall. Let ω0 = √k/m and α = k′/k.

(a) Demonstrate that the equations of motion of the system can be written:

ẍ1 = −(1+α)ω02 x1 +ω02 x2,

ẍ2 = ω02 x1 −(1+α)ω02 x2,

(b) Demonstrate that the normal frequencies of the system are ω = α1/2 ω0 and ω = (2 +α)1/2 ω0.

(c) Demonstrate that the low frequency normal mode is such that the two masses oscillate in phase with the same amplitude, and that the high frequency mode is such that the two masses oscillate in anti-phase with the same amplitude.

The wheel of an engine starts to rotate from rest with uniform angular acceleration. It accelerates angularly for an unknown time (t1) until reaching an angular velocity of 45.13 rad / s, then maintains that angular velocity constant for 37.8 s. The total angle traveled by the wheel in total is 2398.61 rad.

a) What is the angular acceleration with which the wheel began to rotate?
b) What is the time (t1) that the wheel was accelerating?
c) What is the angle traveled by the wheel during acceleration?
d) How many laps did the wheel (revolutions) give? rev

You are a member of a geological team in Central Africa. Your team comes upon a wide river that is flowing east. You must determine the width of the river and the current speed (the speed of the water relative to the earth). You have a small boat with an outboard motor. By measuring the time it takes to cross a pond where the water isnt flowing, you have calibrated the throttle settings to the speed of the boat in still water. You set the throttle so that the speed of the boat relative to the river is a constant 6.00 m/s. Traveling due north across the river, you reach the opposite bank in 20.1 s. For the return trip, you change the throttle setting so that the speed of the boat relative to the water is 8.20 m/s . You travel due south from one bank to the other and cross the river in 11.2 s.

With the throttle set so that the speed of the boat relative to the water is 6.00m/s, what is the shortest time in which you could cross the river?

A mass of 3.8 kg is originally moving at 8 m/s at the top of a frictionless incline which has a length of 6.2 meters and an inclination angle of 56 degrees. It slides down the incline and over a horizontal surface in which a portion of it has friction. The coefficient of kinetic friction is 0.37 and the portion of the surface which has friction is 8 meters. At the end of the horizontal surface is a spring. The mass compresses the spring 0.65 meters before it is stopped. What is the amount of force produced by the spring when the mass is stopped in Newtons?