TBR Physics Section #4 Phase I q12: Equilibrium

[enervate]

---

Members do not see this ad.

The above system is in equilibrium when when x = 1.0cm. If x is changed to 5cm, the rod would:

A. no longer be in translational or rotational equilibrium
B. be in translational equilibrium but not in rotational equilibrium
C. be in rotational equilibrium but not in translational equilibrium
D. still be in both translational and rotational equilibrium

Answer: A (highlight to see)

Why? Obviously Σ(&#964😉 ≠ 0 but wouldn't Σ(F) = 0? If the rod were fixed to the fulcrum, it would still be in translational equilibrium, correct?

 

[eradicator]

The above system is in equilibrium when when x = 1.0cm. If x is changed to 5cm, the rod would:

A. no longer be in translational or rotational equilibrium
B. be in translational equilibrium but not in rotational equilibrium
C. be in rotational equilibrium but not in translational equilibrium
D. still be in both translational and rotational equilibrium

Answer: A (highlight to see)

Why? Obviously Σ(&#964😉 ≠ 0 but wouldn't Σ(F) = 0? If the rod were fixed to the fulcrum, it would still be in translational equilibrium, correct?

The rod isn't in translational equilibrium because the rod will start to rotate clockwise which will cause the masses to accelerate (as what the book explanation says). This technically means that the net force is not zero...due to the acceleration (F=ma) being a non-zero value.

 

[enervate]

Is it safe to assume Σ(F) ≠ 0 when Σ(&#964😉 ≠ 0?