• Support PF! Buy your school textbooks, materials and every day products Here!

Force vectors acted on by two forces

  • #26
kay
60
2
Sorry to disturb, but could we have found the magnitude of the resultant by using the parallelogram law? :confused:
 
  • #27
ehild
Homework Helper
15,408
1,810
Sorry to disturb, but could we have found the magnitude of the resultant by using the parallelogram law? :confused:
Yes, you can.

The magnitude of the sum of wo vectors ##\vec c= \vec a+\vec b## is
##|c|=\sqrt{ ( \vec a + \vec b)^2}=\sqrt {|a|^2 + |b|^2 + 2|a||b| \cos (θ) }##
which is the length of the "long" diagonal of the parallelogram made by vectors ##\vec a## and ##\vec b##. θ is the angle between the vectors. You can also apply the cosine law for the blue triangle.


ehild
 

Attachments

Last edited:

Related Threads for: Force vectors acted on by two forces

  • Last Post
Replies
2
Views
15K
  • Last Post
Replies
1
Views
5K
Replies
4
Views
12K
Replies
1
Views
2K
Replies
16
Views
792
  • Last Post
Replies
5
Views
3K
Replies
5
Views
2K
  • Last Post
Replies
1
Views
1K
Top