When calculating the angular velocity of the Earth as it completes a full rotation on its own axis (a solar day), this equation is represented as: Ï avg = 2Ïrad/1day (86400 seconds), which works out to a moderate angular velocity of 7.2921159 Ã 10 -5 radians/second.
Roof sarking is a membrane that is fitted during tile or metal roof construction. The flexible membrane is usually installed under the battens to provide thermal insulation and to prevent water and dust penetration in the roof space.In bushfire prone areas flying embers cannot enter this space through the roof due to sarking protection.he flexible membrane is usually installed under the battens to provide thermal insulation and to prevent water and dust penetration in the roof space. In bushfire prone areas flying embers cannot enter this space through the roof due to sarking protection.
Typically a Scottish practice, the roofing underlay is laid directly over a series of sarking boards fixed to the roof rafters with the roof slates nailed directly to the sarking boards.he sarking board itself is a barrier to the migration of water vapour and in most situations will require the provision of ventilation to the roof space in accordance with BS5534 (BS5250:2002).