Write an equation for the magnetic field of an electromagnetic wave traveling in vacuum if the amplitude is 0.0028 T and the frequency is 2.0 × 10⁸ Hz. Find the magnetic field when x = 32 cm and t = 6.8 ns.

a) A photon is observed coming from an isolated hydrogen atom with 1.89eV energy. What transition has just been observed?

Select one:a. n=4 to n=2b. n=5 to n=3c. n=3 to n=2d. n=5 to n=4

b) The number of electrons per second ejected from a metal in the photoelectric effect is proportional to

Select one:a. the frequency of the incident light b. the threshold frequency of the material c. the wavelength of the incident light d. the intensity of the incident light

A circular area with a radius of 6.60 cmcm lies in the xx-yy plane.

A) What is the magnitude of the magnetic flux through this circle due to a uniform magnetic field BB = 0.211 TT that points in the +z+z direction?

Express your answer in webers.

B) What is the magnitude of the magnetic flux through this circle due to a uniform magnetic field BB = 0.211 TT that points at an angle of 52.7 ∘∘ from the +z+z direction?

Express your answer in webers.

C) What is the magnitude of the magnetic flux through this circle due to a uniform magnetic field BB = 0.211 TT that points in the +y+y direction?

Express your answer in webers.

A homemade capacitor is assembled by placing two 10 in pie pans 8 cm apart and connecting them to the opposite terminals of a 9 V battery.

(a) Estimate the capacitance.
  pF
(b) Estimate the charge on each plate.
pC
(c) Estimate the electric field halfway between the plates.
V/m
(d) Estimate the work done by the battery to charge the plates.
J
(e) Which of the above values change if a dielectric is inserted? (Select all that apply.)

electric fieldchargework done by the batterycapacitance

Two blocks are connected by a light string that passes over a frictionless pulley as in the figure below. The system is released from rest while m2 is on the floor and m1 is a distance h above the floor.

(a) Assuming m1 > m2, find an expression for the speed of m1 just as it reaches the floor. (Use any variable or symbol stated above along with the following as necessary: g.) vf = Incorrect: Your answer is incorrect. (b) Taking m1 = 6.6 kg, m2 = 3.7 kg, and h = 3.9 m, evaluate your answer to part (a). Correct: Your answer is correct. m/s (c) Find the speed of each block when m1 has fallen a distance of 2.0 m. 4.93 Incorrect: Your answer is incorrect.

1. System Schemas: PLEASE BE DETAILED WITH EXPLANATIONS!

a. Suppose you are sitting in a car that is speeding up. Draw a system schema for this situation. Then draw well-separated force diagrams (free-body diagrams) of the following objects:

- your own body;

- the seat in which you are sitting (apart from the car);

- the car (apart from the seat);

- the road surface where the tires and the road interact.

b) Assume the car has rear wheel drive. Describe each force in words; show larger forces with longer arrows. Identify the Newton's third law pairs. (How are they visible in the system schema?)

c) Explain how the force imparting acceleration to the car originates.

You just purchased a new home and decided to build your hot tub behind it. After several hours of careful work in the field, you figure out that they will need to excavate exactly 5.0m3 of soil. You go out and sub-sample representative spots in the soil as it is excavated and find that it weighed 120g right after you pulled it out of the hole, and then weighed 92g after you dried it out in the oven. Your contractor excavates the site and informs you that exactly 9Mg of soil (as is/wet) were hauled away from your site. Based on this information, answer the following questions: (Show all work/units for full credit!)

A. What was the gravimetric water content of the soil sub-sample (rounded to nearest whole %)?

B. What was the bulk density of the soil (rounded to 2 decimal places)? (hint: use the sub-sample moisture content to calculate the dry weight of the larger mass of soil that came out of the 5.0m3 hole by cross multiplying WETsub/WETbulk X DRYsub /DRY/bulk)

C. What was the % solid space of this soil(rounded to nearest whole %)?

D. What was the % pore space of this soil?

E. What was the volumetric water % of this soil (rounded to nearest whole %)?

F. If this soil were completely saturated with water, how many Mg of wet soil would the contractor have to haul away?

G. If you could compact the soil that was hauled away to its maximum dry density (2.20 Mg/m3) how many m3 of disposal area would be required for it(rounded to 2 decimal places)?

H. What was the % air filled pore space in the intact soil as it was excavated? (hint: subtract volumetric water from total pore space for this).

Determine the reflection coefficient of the pulse amplitude under the following boundary conditions on the right end:

(1) Fixed end

(2) Loose end

A 100kg mass traveling with a velocity of 15m/s on a horizontal surface strikes a spring with a spring constant k = 5 N/m a. Find the compression of the spring required to stop the mass if the surface is frictionless b. Find the compression of the spring if the surface is rough (0.4ku=0)

A proton experiences no magnetic force if it travels in the direction of 30 degrees North of East.
It will experience 8x10^-17 N magnetic force directed downward into the ground if it travels due east at 1000 m/s.

Find the magnitude and direction of the magnetic field.

Two pucks are sliding on a frictionless tabletop. Block A (mass 4.11 kg) is moving to the East (+x direction) at 1.50 m/s. Block B (mass 4.93 kg) is moving to the North (+y direction) at 1.80 m/s. Assume the system to be both Block A and Block B. (Note: It could be useful to make a drawing of the situation.)
What is the x-component of the total momentum of the system before the collision?
What is the y-component of the total momentum of the system before the collision?
What is the x-component of the total momentum of the system after the collision?
What is the y-component of the total momentum of the system after the collision?

Four charges are at the corners of a square

centered at the origin as follows:

7 q at (?4 a,+3 a) ,

9 q at (+4 a,+3 a) ,

?5 q at (+4 a,?3 a) , and

9 q at (?4 a,?3 a) .

A fifth charge 9 q with mass m is placed at

the origin and released from rest

Draw diagrams to indicate qualitatively the position, nature, and size of the image formed by a converging lens of focal length f for the following object distances: (a) infinity, (b) greater than 2f, (c) equal to 2f, (d) between 2f and f, (e) equal to f, (f) less than f.

Please answer those questions. Those are about the magnetic force experiment.

Q1. Discuss how the Helmholtz coils creates a magnetic field and what direction it is (You will have to assume a direction of current for this part).
Q2. Discuss how the magnetic torque is created on the 100 turn coil and what it does.