# 10 members 5 joints

<-- Enter members (m)
<-- Enter joints (j)

A truss has 10 members and 5 joints. Is it:
Statically Determinate
Statically Indeterminate
Unstable

## Statically Determinate?

Is the following equation true:?
2j = m + 3 where
j = joints and m = members

## Plug in j = 5 and m = 10

2(5) = 10 + 3
10 < 13

Since 2j < m + 3, the truss is
Statically Indeterminate

Since 2j < m + 3, the truss is
Statically Indeterminate

### How does the Static Determinacy and Stability Calculator work?

Given a number of joints (j) and a number of members (m), this determines if a truss is statically determinate, statically indeterminate, or unstable
This calculator has 2 inputs.

### What 1 formula is used for the Static Determinacy and Stability Calculator?

1. 2j = m + 3
where j = joints and m = members

For more math formulas, check out our Formula Dossier

### What 4 concepts are covered in the Static Determinacy and Stability Calculator?

joint
formed when two or more surfaces are joined together
stable
A structure which will not topple over easily when acted upon by a load
static determinacy and stability
truss
a structural member usually fabricated from straight pieces of metal or timber to form a series of triangles lying in a single plane. (A triangle cannot be distorted by stress.)