# Mechanics - Moments

> Source: https://ollybritton.com/notes/a-level/maths/topics/mechanics/moments/ · Updated: 2021-10-20 · Tags: mechanics, school, maths, year-2

## Flashcards
##### Why is it good to carefully choose the point where you take moments??
Because you can ignore the rotational effect of any forces acting at that point.

##### ![PHOTO MOMENTS](moments.png) Why is it good to take moments at $R_A$ or $R_C$ here rather than halfway down the rod??
Because you only get 1 unknown.

### 2021-11-17
##### If a rigid body is tilting about a pivot, what can you say about the reaction at any other support??
It is zero.

##### ![PHOTO TILTING](tilting.png) If this rigid body is tilting about $C$, what can you assume about the reaction force at $D$??
It is zero.

### 2022-03-30
##### When giving a moment as an answer, what should you always specify??
Clockwise/Anticlockwise

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