Question

A ladder is more apt to slip when you are high up on its rung than when you are just begin to climb. Why?

• A. When you are high up, the moment of force tending to rotate the ladder about its base increases, while in the latter case, the moment of the force is insufficient to cause slipping
• B. When you are high up, the ladder is in unstable, equilibrium
• C. As you climb up, your potential energy increases
• D. When you are high up, the centre of gravity of the system shifts upwards so the ladder is unstable, while in the latter case the system is more stable

Answer 1

The correct option is A When you are high up, the moment of force tending to rotate the ladder about its base increases, while in the latter case, the moment of the force is insufficient to cause slipping

When we are high up, the moment of force tending to rotate the ladder about is base increases, since the dictance from base increases and we know that $\tau =r\times F$

Hence due to increase in $r$, the moment increases.

While in the latter case, the moment of the force is insufficient to cause slipping because $r$ is very small.