Statics

Identifying Static Situations Objects that do not move linearly (translational motion) or rotate (rotational motion) are static

Equations

Example 40º A box of mass 10 kg is placed 2 m from the left end of a 7 m long horizontal beam. The beam has a mass of 20 kg and is supported by a cable that makes a 40º angle to the beam. What is the tension in the cable?

Fy F T 40º Fx 98 N 196 N

Ladder R Ff Mg FN mg Ff

Ladder Problem A 20 m ladder (mass of 15 kg) is leaning against a frictionless wall and makes a 60 degree angle to the horizontal. What is the minimum coefficient of friction needed between the floor and the ladder to keep the ladder from slipping?

R FN mg Ff

R θ 90-θ mg θ B