A box rests on top of a flat bed truck. The box has a mass of m = 16 kg. The coefficient of static friction between the box and truck is μ_s = 0.76 and the coefficient of kinetic friction between the box and truck is μ_k = 0.61.

1.The truck accelerates from rest to v_f = 18 m/s in t = 14 s (which is slow enough that the box will not slide). What is the acceleration of the box?

2.In the previous situation, what is the frictional force the truck exerts on the box?

3.What is the maximum acceleration the truck can have before the box begins to slide?

4.Now the acceleration of the truck remains at that value, and the box begins to slide. What is the acceleration of the box?

5.Now the acceleration of the truck remains at that value, and the box begins to slide. What is the acceleration of the box?

Three-cylinder capacitor

A capacitor consists of three concentric cylindrical shells with radii R, 2R, and 3R. The inner and outer shells are connected by a conducting wire, so they are at the same potential. The shells are initially neutral, and then some charge is transferred from the middle shell to the inner/outer shells.

a) If the final charge per unit length on the middle shell is λ, what are the charges per unit length on the inner and outer shells?

b) What is the capacitance per unit length of the system?

c) type or neat handwriting for the questions above ( I don't understand cursive a lot) I appreciate your understanding.

I have a pinhole 50 microns in size illuminated by a coherent laser beam. Now, I have a lens (75mm focal length) 1 focal length from this pinhole, what size will the beam be when it is incident on this 75mm lens?

Consider the system of capacitors shown in the figure below (C₁ = 7.00

1. What are the shapes of the following compounds?                                                        (10 pts)                                  

(i)        H₂O                                                 (ii) CO₂                                               (iii) CH₄

A spring mass system with a natural frequency fn = 12 Hz is attached to a vibration table. The table is set to vibrate at 16 Hz, 0.5 g maximum acceleration:

a. What is the amplitude of the table's motion in inches?

b. What is the magnification factor M of this undamped system?

c. What is the maximum displacement of the mass assuming no dampening?

d. What is the maximum acceleration of the mass assuming the packaging can be modeled as a viscous damper with a damping ratio of 0.2?

e. Is the motion of the mass in phase or out of phase with the motion of the table?

benift of small-scale solar photovoltaic power with battery storage ?

1. find (a)electric field and (b)magnetic field of TE waves in a rectangular waveguide.

2. find (a)electric field and (b)magnetic field of coaxial transmission line.

For a ballistic pendulum lab;

Describe in words how you used conservation of momentum in this lab. You must also explain why you were able to use conservation of momentum for this part of the problem

A cat leaps from the ground onto a table that is 1.50 m high. The cat leaves the ground at 8.00 m/s at an angle of 60o from the horizontal.

1. How much time was the cat in the air?

2. Find the cat’s velocity just before it lands on the table?  

In figure, a wheel of radius 0.30 m is mounted on a frictionless horizontal axle. A massless cord is wrapped around the wheel and attached to a 3.0 kg box that slides on a frictionless surface inclined at angle θ = 29° with the horizontal. The box accelerates down the surface at 1.9 m /s ². What is the rotational inertia of the wheel about the axle? (Your answer must be in units of kg.m ² and include 3 digit after the decimal point. Maximum of 5% of error is accepted in your answer. Take g=9.80 m /s ².)

a) How does the magnetic flux through the loop changes as the magnet rotates. Is the flux maximal when the magnet is horizontal or vertical on the screen? Why?

b) How does changing the magnetic flux works to create an emf (potential difference) in the coil, which alternates over time (use the Faraday’s law equation)?

When an AC source is connected across a 11.5-? resistor, the rms current in the resistor is 8.66 A.

(a) Find the rms voltage across the resistor.
V

(b) Find the peak voltage of the source.
V

(c) Find the maximum current in the resistor.
A

(d) Find the average power delivered to the resistor.
W

A tank initially contains 300 gallons of a salt solution made by dissolving 30 pounds of salt in water. A solution containing 0.6 pounds of salt per gallon enters the tank at a rate of 5 gallons per minute. A drain is opened at the bottom of the tank through which the well stirred solution leaves the tank at the same rate of 5 gallons per minute. Let y(t) denote the amount of salt (in pounds) which is in the tank at time t. (A) find out y(t)?( B) how much salt is in the tank after 1/2 hour?