Worksheet: Rotational Motion
KEY
Name___________________
1.
Choose the type of motion that matches each description: translational (T) or
rotational (R)
T
______
All parts of object move together.
R
______
Some parts of object move faster than others.
R
______
Motion is around an axis.
T
______ Object is treated as a single point.
2.
What is center of gravity?
a single point where all of the weight of an object appears to be concentrated
_______________________________________________________________
3.
in the middle
In a uniform bar, where is the center of gravity? _____________________
4.
center
gravity
An object topples over when its __________
of ____________
is outside its
base
support
_________
of ______________.
5.
Why do pigeons move their heads from side to side as they walk?
This motion keeps a pigeon’
s center of gravity over the foot currently on the ground.
6.
Why must you bend forward when carrying a heavy load on your back?
The added load shifts your center of gravity backwards; tilting forwards brings your
center of gravity back into the center of your body and above your feet.
7.
Which of these designs is better for a drink container
that sits on the floor of a car? Explain your answer.
Tilting this container will raise its center of gravity, causing it to fall
back onto its base.
8.
When tilting an object lowers its center of gravity, the object is in (stable, unstable)
rotational equilibrium. This is because the force of gravity will make the object
(continue to topple, tilt back to its original position).
9.
mass
distribution of mass
Rotational inertia depends on _________
and ________________________.
10. Why does a long pole help a tightrope walker keep her balance?
The pole helps to distribute mass farther from the axis of rotation (the tightrope), thus
increasing rotational inertia and resisting rotation.
torque
11. Anything that affects the rotational motion of an object is a ___________.
force
12. Torque depends on the _________
applied and the distance of that force from the
lever
arm
pivot point (called the __________
_______).
PHYSICSFundamentals
© 2004, GPB
7-03a