1. Motion is a process of (a) a change in time, (b) a change in position, (c) a change in weight, (d) a change in mass.

2. Which of the following is a scalar quantity? (a) force, (b) speed, (c) velocity,               (d) acceleration.

3. The time rate of change of velocity is (a) speed, (b) acceleration, (c) friction,            (d) force.

4. In addition to a magnitude, a vector quantity has (a) time, (b) direction,                 (c) length, (d) an average value.

5. Velocity (a) is a scalar quantity,(b) has no direction, (c) is a vector quantity,          (d) has the units of displacement.

6. Which of the following is a unit of acceleration? (a) km/s, (b) ft/s, (c) m/s2,            (d) cm/s .

7. All objects in free fall near the Earth’s surface have the same (a) velocity,              (b) speed, (c) acceleration, (d) weight.

8. Weight (a) is less in magnitude than an object’s mass, (b) is the same as mass,        (c) is a gravitational force, (d) has the units of kilos.

9. Mass is a measurement of (a) volume,(b) inertia, (c) force, (d) weight.                  

    10.For an object in free fall (a) the momentum is conserved, (b) there is zero net   force acting on it, (c) only the gravitational force is considered, (d) there is air resistance acting on it.

    11.If two equal and opposite forces act on an object, the object will (a) increase its inertia, (b) remain at rest or in uniform motion, (c) experience an unbalanced force,   (d) experience an acceleration.

    12.When the net force acting on an object increases, (a) its acceleration remains constant, (b) its velocity remains constant, (c) its speed is zero, (d) a change in speed and / or direction occurs.

     13. Work is equal to the (a) force times time, (b) mass times acceleration, (c) force times distance, (d) force divided by distance.

      14.The unit of work is (a) m/s, (b) N, (c) watt, (d) joule.

      15.The time rate of doing work is (a) momentum, (b) energy, (c) power, (d) force.

      16. The watt is a unit of (a) work, (b) momentum, (c) energy, (d) power.

      17. The energy of motion is called (a) potential, (b) inertial, (c) kinetic, (d) power.

      18. The energy of position is (a) work, (b) heat, (c) potential energy, (d) momentum.

      19.The impulse applied to an object is equal to the change in its (a) acceleration,          (b) velocity, (c) kinetic energy, (d) momentum.

       20. The impulse is equal to the (a) force times distance, (b) force times time, (c) mass times acceleration, (d) mass times velocity.

      21. The unit for angular acceleration in the metric system of units is (a) radians/s,        (b) m/s2, (c) degrees/s, (d) radians/s2.

     22. Newton’s second law of rotational motion states that torque equals (a) moment of inertia times angular velocity, (b) mass times distance, (c) angular velocity times time, (d) moment of inertia times angular acceleration.

     23. The perpendicular distance from the axis of rotation to a line along which a force acts is known as the (a) torque, (b) moment of inertia, (c) lever arm, (d) momentum.

     24. The time rate of change of angular velocity is known as angular (a) momentum,    (b) inertia, (c) acceleration, (d) velocity.

      25.The pressure in a liquid depends on (a) the weight density of the liquid, (b) the depth in the liquid, (c) the mass density of the liquid, (d) all of the preceding.

     26. The unit of pressure in the metric system is (a) pa/m, (b) Nm, (c) N/m2, (d) m/s.

     27.   Pressure may be decreased by (a) decreasing the force and area by the same factor, (b) decreasing the area of contact, (c) increasing the area of contact, (d) increasing the applied force.

     28. The buoyant force is described by (a) Bernoulli’s principle, (b) streamline flow,     (c) Pascal’s principle, (d) Archimedes’ principle.

       29. A mechanical advantage can be obtained by the application of (a) Archimedes’ principle, (b) Bernoulli’s principle, (c) surface tension, (d) Pascal’s principle.

       30. The rising of a hot air balloon is explained by (a) Pascal’s principle, (b) Bernoulli’s principle, (c) Archimedes’ principle, (d) none of these.

        31.The velocity of a car changes from 60 m/s to 45 m/s in 5 seconds. The magnitude of the car’s acceleration is (a) 21m/s2, (b) 35 m/s2, (c) 3m/s2, (d) 5m/s2.

        32.  A clam dropped by a sea gull takes 4 seconds to hit the ground. What is the sea gull’s height above the ground at the time the clam was dropped? (a) 90 m,           (b) 45 m , (c) 78 m, (d) 30 m.

         33. A single force of 63 N acts on a 7 kg block. What is the magnitude of the acceleration of the block? (a) 70 m/s2, (b) 9 m/s2, (c) 10 m/s2, (d) 5m/s2.

         34.  A net force of 15 N acting on a wooden block produces an acceleration of      3 m/s2 for the block. What is the mass of the block? (a) 18 kg, (b) 45 kg, (c) 5 kg,     (d) 12 kg.

         35.  A net force of 100 N accelerates a 20 kg block over a distance of 3 m. What is the work done by this net force? (a) 600 J, (b) 200 J, (c) 300 J, (d) 100 J.

        36. A 2 kg block is moving at a constant speed of 3 m/s. What is the kinetic energy of the block? (a) 6 J, (b) 12 J, (c) 9 J, (d) 18 J.

         37. A 7 N force imparts an impulse of 42 Ns to an object. The force acts on the object for a period of (a) 0.6 s, (b) 49 s, (c) 6s (d) 10 s.

          38.  What is the magnitude of the change in momentum produced when a force of 3 N acts on a 10 kg block for 5 seconds? (a) 1.5 kgm/s, (b) 3 kgm/s, (c) 50 kgm/s,          (d) 15kgm/s.

          39. A force of 30 N pushes down on the movable piston of a closed cylinder containing a gas. The piston’s area is 0.2m2. What pressure does this produce in the gas? (a) 6 pa, (b) 15 pa, (c) 60 pa, (d) 150 pa.  

           40. A block of wood of uniform density floats so that 35% of its volume is above water. The density of water is 1000 kg/m3. What is the density of the block?               (a) 350 kg/m3, (b) 750 kg/m3, (c) 650 kg/m3, (d) 150 kg/m3 .            

Sketch the typical structure of bands for a metal and for a semiconductor indicating which states are filled. Why do metals show the full rainbow upon thermal emission but semiconductors give off dominantly just one color?

Some beetles have wings that appear to “change color” and are “reflective” in different colors. Explain how this occurs?

A wire 80 cm long carries 11 A of current. From this wire, a loop of 90-turns is made and placed in a magnetic field of 6.50 Tat an angle of 35˚. In first experiment, a square loop is formed and in the second experiment, a circular loop is formed with same number of turns. Calculate the torque in each loop. Which loop produces more torque-the circular loop or the square loop? What is the reason for this change of torque in both loops?   

Another type of external combustion steam engine in the Rankine cycle engine. You are told a Rankine engine will be operated in the following manner. The engine will use 0.46 kilomoles of water vapor. The water vapor is initially at 1.5 atm in a 10 m³ vessel. The water vapor is compressed isobarically to 1/10^th of its original volume. The water vapor is then isochorically pressurized to 5 atm. The water is then isobarically expanded to a volume of 4.23 m³. Finally the water vapor is allowed to adiabatically expand back to its original pressure and volume. Treat the water vapor as a diatomic gas.

(R = 8314 J/(kilomole K); 1 atm = 101325 Pa)

a.) Draw the PV diagram for the Rankine cycle.

b.) Calculate the work done by the engine for one complete cycle.

c.) Calculate the heat absorbed by the engine.

d.) Calculate the efficiency of the heat engine.

e.) Compare this efficiency to a Carnot cycle operating between the two most extreme temperatures achieved by the engine.

EXPLAIN ANSWERS PLEASE

The electric field intensity in a source-free, dielectric medium is given as ? = 2?0 sin(??) ?????⁡?̂ V/m.

Determine

(a) the magnetic field intensity using Maxwell’s equation from Faraday’s law, and

(b) the displacement current density in the medium.

What is the advantage of having smaller regions for data encryption on a CD or DVD?

Amplitude (x0)=5 cm

Find the spring constant and value of q

1) How does the formation of a plasma core lead to nuclear fusion in a star? Why is hydrogen the first element to fuse?

2) What is the last element to fuse in a low mass star? What element has built up around the core but does not fuse? What type of object does a low mass star become to end its life cycle?

3) What element builds up around the core of a high mass star but does not fuse? Why does this lead to a massive explosion?

4) What is electron degeneracy and neutron degeneracy? When are they important in the evolution of stars?

7 Energy

7.1 Equations

•Kinetic energy: KE=1/2mv23 •Potential energy: PE=mgh

•total energy: E=KE+PE•work: W=Fd=∆E. If force and distance are perpendicular, W=0. If opposite,W¡0.•power: P=∆E∆t

7.2 Skills

•Know how to find velocities or heights of objects, using conservation of energy and knowing information about initial/final states.

•Know how to find energy of object and thus velocity after a force has done work on it.

•Use power to find how quickly an object’s energy changes

.8 Rotation

8.1 Equations

•Rotational velocity:ω=∆θ∆t

•Rotational acceleration:α=∆ω∆t•torque:τ=rForτ=Iα; if r and F are parallel, torque is zero

•Rotational KE=1/2Iω2•Angular momentumL=mvr, orL=Iω8.2Skills

•Same types of problems as motion, but with angular variables: Givenαand ∆t,find ∆θ,etc.

•Know how to find the torque on an object for different forces and distances.

•Use rotational KE in conservation of energy problems when an object is spin-ning/rotating

•Use Conservation of angular momentum for objects spinning/rotating, to find ini-tial/final momentums.

•Given a torque, find the angular acceleration made for an object with inertia I

A long conducting pipe has a rectangular cross section with sides of lengths a and b. One face of the pipe is maintained at a constant potential V = V0 while the other 3 faces are grounded (V = 0). Using separation of variables, find the potential for points inside the pipe V (x,y).

A long straight wire runs along the y axis and carries a current of 1.80 A in the +y direction. Determine the magnitude and direction of the magnetic field along the line. x = 21.0 cm.

Magnitude ?? T

Direction ??? ( +.- )(I,J,K) ??

Two long current-carrying wires run parallel to each other and are separated by a distance of 2.00 cm. If the current in one wire is 1.45 A and the current in the other wire is 3.35 A running in the opposite direction, determine the magnitude and direction of the force per unit length the wires exert on each other.

Magnitude ??? N/m

Direction ??? ( Towards or Away from each other)

Cesium has a binding energy (“work function”) of 1.8 eV. When cesium is illuminated with a light of a certain wavelength, the electrons ejected from the surface have a kinetic energy of 2.2 eV. What is the wavelength (nm) of the light?