Download Net Work WhiteBoard Problems

WHITEBOARD TIME !!
LET’S DO SOME
F·d ·cos  !!!
A warehouse worker has just unloaded a 120 kg crate full
of spare parts. The worker pulls the crate at
constant velocity exerting a constant force of 294 N
through a displacement of 100 m.
1.
2.
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6.
Draw a motion diagram
Draw a force Diagram.
Find the magnitude of all forces exerted on the crate.
Find the work done by all forces on the crate.
Find the total work (net work) done on the crate.
Draw a graph F vs d. (find the area of the graph).
A 0.160 kg hockey puck slides along an ice rink. It slows
down to stop over a displacement of 20 m.
Note: The coefficient of kinetic friction between the puck
and ice is 0.02 .
1.
2.
3.
4.
5.
6.
Draw a motion diagram.
Draw a force Diagram.
Find the magnitude of all forces exerted on the puck.
Find the work done by all forces on the puck.
Find the total work (net work) done on the puck.
Draw a graph F vs d. (find the area of the graph).
A tractor pulls a 1500 kg sled of firewood. The force exerted
by the rope on the tractor is 5000 N @ 36.9º. The sled
moves at a constant velocity.
1. Draw a force Diagram.
2. Find the magnitude of all forces exerted on the sled.
3. Find the work done by all forces on the sled.
4. Find the total work (net work) done on the sled.
5. Find the coefficient of kinetic friction between the sled
and the ground.
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7.
8.
Draw a graph FTX vs d.
Find the area between the graph and the axis,
between dx=0m and dx=100m.
What is the meaning of this area?