Texas Instruments TI-83 Plus Manual page 77

Calculating a Cross Product
The cross (vector) product of two vectors V1 and V2 is a vector
whose magnitude is calculated by the equation
× =
V1 V2
When you find a cross product of two vectors, the resulting
vector is not displayed graphically because that requires
3-dimensional plotting capability. However, the magnitude of the
vector is displayed. If the magnitude is a negative value, the
vector lies along the negative z-axis. If the magnitude is positive,
the vector lies along the positive z-axis.
Torque is a vector quantity defined by the cross product of a
position vector and a force vector,
radius about the axis of rotation.
 Example: Find the magnitude and direction of the torque
imparted to a nut by applying a force of 20 N perpendicularly at
the end of a 10 cm wrench.
20 N of force
10 cm
TI-83 Plus Science Tools Application
, where E is the angle between V1 and V2.

( )( )
V1 V2 sin
r r
r
= ×
, where R is the
R F
Page 77