# Tension in rope with pulley

1. Aug 4, 2015

### oreo

Suppose a pulley is lifting a mass through rope so the rope is applying force to mass in form of Tension. Is the rope also applying that force to pulley i.e Is pulley being acted upon by Tension??

2. Aug 4, 2015

### A.T.

Tension is internal to the rope. The rope exerts contact forces on the pulley.

3. Aug 4, 2015

### oreo

Hm but why we express Tension by Two arrows?

4. Aug 4, 2015

### A.T.

Because the magnitudes of the forces exerted tangentially by the string ends are equal to the tension in the string, which by itself is a scalar.

5. Aug 4, 2015

### Nidum

Tension in lifting rope is reacted by various means depending on the set up .

Simple cases
:
Rope continues around pulley to another end which is being pulled to lift the weight
Tensions in the two rope ends are reacted by the pulley bearings .

Rope wraps around a winch drum which is being powered to lift weight .
Tension in lifting rope is reacted by torque of motor acting on drum and by drum bearings .

Too many cases of pulley arrangement to give a general answer .