A bicycle wheel has a diameter of 63.9 cm and a mass of 1.86 kg. Assume that the wheel is a hoop with all of the mass concentrated on the outside radius. The bicycle is placed on a stationary stand and a resistive force of 123 N is applied tangent to the rim of the tire. (a) What force must be applied by a chain passing over a 8.96 cm diameter sprocket if the wheel is to attain an acceleration of 4.42 rad/s2? (b) What force is required if the chain shifts to a 5.50 cm diameter sprocket?

How many grays is this?Part A

A dose of 4.7 Sv of γ rays in a short period would be lethal to about half the people subjected to it.

Part b

What is the energy released in the fission reaction of the equation n+23592U→9440Zr+13952Te+3n? The atomic masses of 23592U, 9440Zr, and 13952Te are 235.043930 u, 93.906315 u , and 138.93473 u respectively, and the mass of a neutron is 1.008665 u.

Physics 100 – Uniform Motion Page 1 of 6
SAN DIEGO MESA COLLEGE Name_________________________
PHYSICS 100 LAB REPORT Date __________Time___________
Partners ______________________
TITLE: Uniform Motion ______________________________
______________________________
______________________________
Objective: To determine the equation of motion for a toy tractor.
Theory: The motion of an object is described by the change of it's position with respect to time,
as measured from a start point for it's position and it's time ( i.e. at x=0 and t=0). The
mathematical relationship for an object's position as a function of the time it reaches
that position is called the object's equation of motion. The simplest equation of motion
is for motion without acceleration. This motion is called uniform motion.
Equipment: motorized cart tape timer mount
tape-timers 1 1/2 meter strips
meter-stick brick
masking tape
Setup:
Paper strip 1.5 meters long
Masking tape
Brick
C(caarbrboonn p saidpe ru dpi s)k
Tapper
M o ctaortiz ed
Physics 100 – Uniform Motion Page 2 of 6
Technique: The tape timer has a circular piece of carbon paper and a tapping mechanism. The
tapper taps on the carbon paper specific number of times per second. As the toy tractor
moves, the tape timer puts marks on the paper strip at regular time intervals. The
amount of time between marks (the Δt) is decided by which direction the switch on the
timer is moved when it is turned on. There are two settings 10Hz and 40Hz. We will be
using the 10Hz setting for a Δt = 0.1seconds. The tractor will move a certain distance
Δx between each mark. These two sets of values will give us the data we need to get
the equation of motion.
Procedure: Turn the tractor on temporarily to see which direction it will move.
Face it so it will move away from the tape timer.
Get one of the long paper strips.
Feed one end through the first plastic slot, then in between the silver metal plate and the
circular piece of carbon paper, and out through the other plastic slot. If it's not feeding
easily, slightly bend a small portion of the end of the paper strip. This might help.
Take a small piece of masking tape and tape the end of the paper strip nearest to the
timer to the top of the tractor.
Place the tractor near the tape timer, but leave enough room to lift the tractor off the
table a little bit (you'll lift it later).
Pull the rest of the tape out the back of the tape timer so that it is hanging over the edge
of the table.
Have one partner lift the tractor off the table enough so that they can turn the tractor on.
Have another partner on the opposite end of the table ready to stop the tractor.
Have a third partner move the switch on the tape timer to the 10Hz position. The timer
should start clicking.
Have the person with the tractor turn it on, aim it towards the brick and set it on the
table.
Once the tractor gets to the other side of the table, move the timer's switch to the off
position to turn it off.
Remove the paper strip from the tractor and turn it over. Make sure the marks made by
the timer are dark and visible.
If they are easily visible, then you are ready to start the analysis. If not, try rotating the
circular piece of carbon paper and run through the procedure again. If this still doesn't
produce visible marks, ask the instructor for help.
Analysis: Look at the marks (dots) on your strip.
The beginning of your strip is the side that was attached to the tractor. The first few
marks probably won't look evenly spaced.
Choose and circle the first dot, after skipping several, which appears sharp and is
evenly spaced with its neighbors. This is dot #1 which occurs at t = 0 sec. and has a
starting position of x = 0 cm.
Lay the paper strip along a meter stick or ruler and use masking tape to attach the first
dot you choose for t = 0 and x= 0 to the zero end of your meter stick or ruler.
Physics 100 – Uniform Motion Page 3 of 6
Record the position of where each dot is along the ruler or meter stick.
Calculate the distance interval between each dot and the dot before it. The distance
interval is the position of each dot minus the position of the dot before it. The distance
interval is also known as Δx.
Dot # Position
(cm)
Time
(Ticks)
Distance
Interval
(cm)
Ave.Velocity
In interval
1 0.0 0 (cm/sec)
2 1
3 2
4 3
5 4
6 5
7 6
8 7
9 8
10 9
The average velocity that the object obtains during an interval of one tick is the distance
interval traveled during that one tick divided by the time elapsed (one tick). To
calculate the average velocity, divide the distance interval by one tick.
This gives you units of cm / tick.
To convert this to a usable number, you will need to multiply this number by the
Number of ticks per 1 second.
There are 10 ticks per second.
This will give you units of cm / sec.
Fill in your table with each of the average velocities.
Physics 100 – Uniform Motion Page 4 of 6
Because the motion is uniform, the average velocity over all the intervals can be found
by adding up all the average velocities, and dividing by the total number of average
velocities intervals.
Record this value below the average velocity column on the data sheet.
Analysis: The equation of motion is found by plotting the distance (in cm, on the y-axis) as a
function of time (in ticks, on the x-axis).
Plot this on the linear graph paper provided in your lab packet.
Calculate the slope of your graph, showing all work including units, in the space
provided below.
(Dfinal - Dinitial) / (Tfinal - Tinitial) = slope
Where D is distance in cm and T is the time in ticks
Convert this slope to cm / second using the same conversion as you did for the average
velocity.
SLOPE FROM GRAPH: CONVERSION:
Calculate the percent difference, in the space provided below, between the average
velocity from the data sheet and the slope of the graph, using the formula:
% difference = (difference between two experimental values / the larger of two values)
x 100
What name is given to the constant (the slope of the graph) which relates the distance
traveled by the tractor and the time it took to get to that distance?
Physics 100 – Uniform Motion Page 5 of 6
Write the equation of the graph, in the form y = mx + b. in the space below. Where y is
the variable plotted on the vertical axis and x is the variable plotted on the
horizontal axis, m is the slope of the graph, and b is the vertical intercept. The vertical
intercept, b, will be close enough to zero to be neglected.
Don't forget to include units in your equation.
Use this equation to calculate, showing all work including units in the space provided
below, how far the tractor would travel in 45 seconds.
How many meters is this? Show your work in converting the units.
How many yards is this? Show your work in converting the units.
Analysis:
Use this equation of motion to predict how many MINUTES it would take the tractor to
Travel 11.78m which is the length of the lab room.
Show all your work below including unit conversions.
Physics 100 – Uniform Motion Page 6 of 6
Summary of Results:(What is the equation of motion for the tractor, in words)?

The mass of a particular eagle is twice that of a hunted pigeon. Suppose the pigeon is flying north at ??,2=18.1vi,2=18.1 m/s when the eagle swoops down, grabs the pigeon and flies off. At the instant right before the attack, the eagle is flying toward the pigeon at an angle ?=40.3θ=40.3° below the horizontal and a speed of ??,1=37.9vi,1=37.9 m/s.

What is the speed of the eagle immediately after it catches its prey?

What is the magnitude of the angle, measured from horizontal, at which the eagle is flying immediately after the strike?

A heat engine takes 0.350 mol of a diatomic ideal gas around the cycle shown in the pV-diagram of the figure (Figure 1) . Process 1?2 is at constant volume, process 2?3 is adiabatic, and process 3?1 is at a constant pressure of 1.00 atm. The value of ? for this gas is 1.40.

Part B

Find the volume at points 1, 2, and 3.

Enter your answers numerically separated by commas.

Part C

Calculate Q, W , and ?U for the process 1?2.

Enter your answers numerically separated by commas.

Part D

Calculate Q, W , and ?U for the process 2?3.

Enter your answers numerically separated by commas.

Part E

Calculate Q, W , and ?U for the process 3?1.

Enter your answers numerically separated by commas.

A cube with mass M slides down a frictionless curved incline as shown in the
figure below. It has a completely inelastic collision with another cube m at the bottom that is

A diver springs upward from a board that is 3.02 meters above the water. At the instant she contacts the water her speed is 9.15 m/s and her body makes an angle of 77.2° with respect to the horizontal surface of the water. Determine her initial velocity.

A block is placed on a frictionless ramp at a height of 12.5 m above the ground. Starting from rest, the block slides down the ramp. At the bottom of the ramp, the block slides onto a frictionless horizontal track without slowing down. At the end of the horizontal track, the block slides smoothly onto a second frictionless ramp. How far along the second ramp does the block travel before coming to a momentary stop, as measured along the incline of the ramp? After the block comes to a complete stop on the second ramp, it will then begin moving back down the second ramp. What is the speed of the block when it is 8.75 m, vertically, above the ground?

A film of soapy water (n = 1.33) on top of a sheet of crystalline quartz has a thickness of 168 nm. What wavelength is most strongly reflected if it is illuminated perpendicular to its surface? (This is the apparent color of the soapy film.)

1. Give several examples of cogeneration and heat pumps. Describe how they work and why they save energy.
2. Can the waste heat from nuclear plants do useful work? What happens to the wasteheat from power plants? How do the First and Second Laws of Thermodynamics apply to these processes?
3. Find numerical examples of energy usage and thermodynamic computations of efficiency. Use the web to compare the efficiencies of several power production processes. Which are in use and which are planned?

Two cars start from rest at a red stop light. When the light turns green, both cars accelerate forward. The blue car accelerates uniformly at a rate of 3.6 m/s² for 4.4 seconds. It then continues at a constant speed for 8.1 seconds, before applying the brakes such that the car

A pen contains a spring with a spring constant of 208 N/m. When the tip of the pen is in its retracted position, the spring is compressed 5.60 mm from its unstrained length. In order to push the tip out and lock it into its writing position, the spring must be compressed an additional 6.90 mm. How much work is done by the spring force to ready the pen for writing? Be sure to include the proper algebraic sign with your answer.

1. What is the weight of a 87.4 kg object? w=?

2.What was the average speed in km/h of a car that travels 798 km in 6.1h?

3. What net force is needed to give a 22 kg grocery cart an acceleration of 2.3 m/s² ?

4.Suppose a radio signal travels from Earth and through space at a speed of 3.0 × 10⁸ m/s. How far into space did the signal travel during the first 38.7 minutes?

5. How far away was a lightning strike if thunder is heard 5.23 seconds after seeing the flash? Assume that sound traveled at 350.0 m/s during the storm.

6.What is the acceleration of a car that moves from rest to 19.1 m/s in 10.0 s?

7. How long will be required for a car to go from a speed of 15.6 m/s to a speed of 26.7 m/s if the acceleration is 3.0 m/s²?

Ref: Yang

A box with mass m is dragged across a level floor having a coefficient of kinetic friction ?k by a rope that is pulled upward at an angle ? above the horizontal with a force of magnitude F.

Part A

In terms of m, ?k, ?, and g, obtain an expression for the magnitude of force required to move the box with constant speed.

Part B

Knowing that you are studying physics, a CPR instructor asks you how much force it would take to slide a 90-kg patient across a floor at constant speed by pulling on him at an angle of 25? above the horizontal. By dragging some weights wrapped in an old pair of pants down the hall with a spring balance, you find that ?k=0.35. Use the result of part A to answer the instructor's question.