The Coriolis effect
£R.E. Tremblay
All rights reserved
A projectile fired from the
equator, straight north, is also
moving east at 1000 mi/hr.
£Because the target is moving east
slower, the projectile will land to the
right of the target.
Coriolis effect
£If it takes the projectile 1 hr to
reach its target, it will be 200
miles east of the target.
1000 mi/hr east
800 mi/hr east
Coriolis effect
£A projectile crossing lines of latitude
in the northern hemisphere, will land
right of its target.
800 mi/hr east
1000 mi/hr east
Angular velocity is the rate at
which an object rotates
ω is the symbol used for angular velocity
Coriolis effect
£A projectile crossing lines of latitude in the
southern hemisphere will curve to its left.
1000 mi/hr east
800 mi/hr east
2 pts. Extra credit
£Fill the bath tube and let the water sit for
15 minutes. Put a floating object in the
water and pull the plug.
Will the projectile hit its target?
£Yes, if we have a flat earth.
£Which way does the water rotate?
X
800 mi/hr
800 mi/hr
A little vector addition
£Actual path is to the
right of the target.
Projectile
fired north
200 mi/hr east
Resultant path
Centripetal force
£The door pushes the
passenger toward the center.
V
V
F
c
Centripetal acceleration
£Acceleration toward the center of
the circle. What two things effect
the centripetal acceleration?
V
a
c
a
c
a
c
R
Centripetal force
£Force toward the center of the circle.
R
F
c
V
Why did Batman shoot the
cable at the light post?
Centripetal force
£Force toward the center of the circle.
R
F
c
V
Batmobile
Torque-the turning effect of a
force
£Torque is the product of the
perpendicular component of the force
and the distance to the pivot.
F
d
pivot
Torque and force are not the
same thing.
£Say it with me!
Moment of inertia
M
1
M
2
d
1
d
2
Center of rotation
Moment of inertia is an object’s
resistance to a change in its
angular velocity, ω
£Angular velocity, ω, is the rate at
which an object is rotating.