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.
Roof cleaning contractors who use sodium hypochlorite (chlorine bleach) mix it in high concentrations with other chemicals such as trisodium phosphate, also known as TSP. They spray it on the roof and wait for it to dry and then re-apply it several times as needed. Stains and moss or lichens that donât come off on the day of treatment may eventually come off with rain in the months to come.