Homework - 10/18/10

A box with a mass of 3 kg is resting on an incline as shown above. The box is released from rest. (a) Determine the acceleration of the box down the ramp. (b) Determine how much time it will take the box to reach the bottom of the ramp if the ramp is 2 meters long. (c) Determine the speed of the box at the bottom of the ramp.

Homework - 10/15/10

Before his foray into teaching, Mr. Aul owned a very famous sign hanging company. He held many contracts with companies such as ENRON, Bear Stearns, Lehman Brothers, and Halliburton. The history of his career is cloudy. Mr. Aul personally hung the sign infront of his headquarters. The picture is seen above. Each cable can only support 100 N of tension and the sign has a mass of 15 kg. Find the tension in each of the cables and determine how good of a job Mr. Aul did. If the cables break, in what order do they break?

Homework - 10/13/10

Three masses are connected and hanging from the ceiling.

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(a) Determine the tension in each rope.

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The top string is then untied from the ceiling and is pulled upward with a constant force of 600 N.

(b) Determine the acceleration of each block.

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(c) The tension in each rope.

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(d) Compare the tensions from part c to the tensions from part a. Did the tension in each rope change? Was this what you would expect? Explain.

Homework - 10/4/10

A cannon is aimed at a building with an angle of 35 degrees as shown above (it's ok to feel jealous of my Paint skills). The cannon is placed 516 meters from the base of the building. If the cannon ball is fired with an initial speed of 100 m/s, determine the following quantities:

a. How high up on the building will the cannon ball land?

b. What is the cannon ball's velocity just before it strikes the building?

Assume that air resistance is negligible and ignore the initial height of the cannon.

Homework - 9/28/10

A baseball is launched horizontally from a hillside as shown above. The baseball is thrown with an initial speed of 12 m/s and lands 41.6 meters down the hill, L.
a. Determine how long the ball is in flight between points P1 and P2.
b. Determine the speed of the ball just before it strikes point P2.

Homework - 9/20/10

A bear is at a local park, drowning his sorrows the way he knows best - by drinking a mug of honey. Sad that his bear family has deserted him and that his bloodlust for humans has made him a fugitive, he slides the mug down the table in frustration. The mug slides off the table horizontally and strikes the ground 1.40 meters from the base of the table. If the tabletop is 0.86 meters high, what velocity did the mug have when it left the table? What is the mug's speed and direction just before it hits the ground.

Homework - 9/15/10

The position function below represents a rock thrown off a cliff.

a. What is the rock's displacement after the first 10 seconds of its flight?
b. What is the rock's velocity as a function of time?
c. What is the rock's velocity after the first 10 seconds? (Write the vector form, then find the magnitude and direction.)
d. What is the rock's acceleration as a function of time?
e. What is the rock's acceleration after the first 10 seconds?
f. Does your answer to part e make sense? Explain.

Homework - 9/2/10

A wealthy businessman has been reduced to taking the bus to work. The bus driver, assuming that a businessman certainly wouldn't be waiting for a bus, passes up the bus stop, continuing with a constant velocity of 20 m/s. The businessman starts running from rest, but can only accelerate at 1.5 m/s2. How much time will it take the man to catch the bus? Also, how far did he have to run?


At the end of this problem, explain whether this is a reasonable answer or not and explain how you know. You could also explain if it would even be possible for a human to cover that distance in that time.

Homework - 8/31/10

The diagram shown above represents two airtrack carts that are about to collide. Cart A is moving and cart B is at rest. After the collision, Cart B's position was marked every 0.1 seconds and is also shown above.


a. Based on the data given for Cart B's position create an accurate position-time graph.

b. Create a general velocity-time graph that represents Cart B's motion. You may reference the x-t graph to help create the velocity graph. (No scale needed)

c. Shade the area under the curve for the v-t graph, state what it represents, and explain what value it should have.

(READ: You need to click on the image to see a larger version)