Transcript Document

A pendulum swings from its end point on the left
(point 1) to its end point on the right (point 5). At
each of the labeled points,
* draw and label ar and at using the correct relative
lengths,
* draw and label a total acceleration vector.
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A car has tires with a diameter of 58 cm. One of the
tires has a chalk mark at the edge. When the car is
moving at 25 m/s,
•What is the period of the chalk mark’s rotation?
•What is the tire’s angular velocity?
•What is the tire’s radial acceleration?
•What are the tire’s tagential and angular
accelerations?
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
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The car speeds up from 25 m/s to 30 m/s in 5 seconds.
During this time what are the
•
tangential acceleration
•
angular acceleration
of the chalk mark on the edge of the tire?
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
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A person is hit in the head (mhead = 5.0 kg) by a
ball that pushes with 45 Newtons of force. How
fast will their head accelerate while in contact with
this ball?
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
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For each of the following situations draw a free-body
diagram for the underlined object. Draw a net force
vector off to the side.
•A cup sits on the desk
•A block is at rest on an incline
•A piece of paper has just been dropped (vi=0)
•A piece of paper has been falling for a while
•Kristine is jumping up
•Kristine is pushing a cart
•A book is pressed against the wall
•A box is sitting still in the back of an accelerating truck
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A 1000 kg steel beam is supported by two ropes.
What is the tension in each rope?
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QUIZ (to turn in)
You’re pushing your grandfather in his wheelchair (m
= 95 kg) down a dry concrete sidewalk at 3 m/s. How
hard do you have to push to keep the wheelchair
moving at this speed?
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
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A car’s engine provides a force of 1900 N to
accelerate the 1100 kg car. Neglecting drag but not
rolling friction, how long should it take this car to
reach 20 m/s? (µr = 0.02 for rubber on concrete)
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
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TO TURN IN:
•Draw a free body diagram for the shuttle during liftoff
•Use Newton’s 2nd law to create an equation for the
shuttle’s thrust
•Analyze the shuttle’s motion using the video and
sketch graphs of its position, velocity and acceleration
•Use information from the analyzed motion and the
known shuttle mass to find the shuttle’s thrust.
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