22-02-2013, 10:09 AM
Vector
Vector.ppt (Size: 287 KB / Downloads: 61)
Defining Vector’s
The physical quantities which have both
magnitudes as well as direction.
e.g, displacement, velocity, force, weight,
acceleration etc.
When we change the direction of vector’s,
its magnitude also changes.
How to represent a vector?
Draw a line with a arrow on its head, then drop
another line and repeat it. Now, join these two
lines such that the head lies in the manner as
shown
Vector Algebra.
Vector Addition:
Suppose 3 forces act on an object at the same
time. Fnet is not 15 N because these forces aren’t
working together. But they’re not completely
opposing each either. So how do find Fnet ? The
answer is to add the vectors ... not their
magnitudes, but the vectors themselves. There
are two basic ways to add vectors w/ pictures:
Tip to tail method
Parallelogram method
Parallelogram method
This time we’ll add red & blue by placing the tails together and drawing a parallelogram with dotted lines. The resultant’s tail is at the same point as the other tails. It’s tip is at the intersection of the dotted lines.