posted by kevin on .
A 90 kg rock climber is stationary off the side of an overhanging cliff hanging onto her climbing rope. Another rope is tied to her foot and is attached at the other end to her 30 kg rock-climbing dog, also hanging out 2 m below her. Tied to the dog’s foot is yet another rope that is attached to the dog’s favorite 2 kg stick, 1.5 m below. What is the tension in the rope that is holding up the climber?
When the bodies are at rest, the tension in the ropess just equal the weight that is suspended beneath them.
The lower body (the stick) has gravity down of m3•g=2•9.8=19.6 N and the tension (T3) in the lower string is
T3 = 19.6 N.
The rope between the climber and the dog:
T2= (m3+m2)g=32•9.8=313.6 N.
The upper rope: