Book push Forces problem

  • Thread starter vanitymdl
  • Start date
  • #1
64
0

Homework Statement


A 0.407 kg book rests at an angle against one side of a bookshelf. The magnitude and direction of the total force exerted on the book by the left side of the bookshelf are given by:

Force Left = 2.17 Newtons and θ=59 degrees

What must the magnitude and direction of the total force exerted on the book by the bottom of the bookshelf be in order for the book to remain in this position?

Force book = ___?___Newtons
θ = ___?___degrees


Homework Equations





The Attempt at a Solution



Sum of forces in x:

2.17sin(59) - Fcos(θ) = 0 => Fcos(θ) = 1.86

Sum of forces in y

2.17cos(59) + Fsin(θ) = 0 => Fsin(θ) = -1.1176

tan(θ) = (-1.1176)/(1.86) => θ = 211 degrees

F = 2.17 N

this is wrong though
 

Answers and Replies

  • #2
rcgldr
Homework Helper
8,749
553
The sum of the forces in y must counter the force exerted by gravity, which is m g.
 
  • #3
64
0
So I was in the right track?
I just need to change my formula to 2.17cos(59) + Fsin(θ) = mg
 
  • #4
rcgldr
Homework Helper
8,749
553
Is the 59 θ the angle from vertical or the angle from horizontal?
 

Related Threads on Book push Forces problem

  • Last Post
Replies
9
Views
5K
Replies
11
Views
6K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
1
Views
1K
Replies
2
Views
588
Replies
1
Views
807
  • Last Post
Replies
2
Views
4K
  • Last Post
Replies
19
Views
8K
  • Last Post
Replies
1
Views
4K
  • Last Post
Replies
11
Views
8K
Top