Satyavrat Sarangi

For those who said that their bluetooth not working in inspiron 15 3521 first check your bios verson if it is A12 then you have to downgrade it link for A11 given below Click here for A11 Now install your wireless driver, it will never ask you to activate Bluetooth using wireless switch. But if asked then simply activate by Fn+F2 key. Any Question please ask in comments.

Use the following formulas to convert average roughness (Ra) to other commonly used surface roughness parameters: R t = R a x 8.7 R z = R a x 7.2 R z ISO = R a x 7.6 R max = R a x 8.0 R p = R a x 3.6 RPM = R a x 2.9 RMS = R a x 1.1 The conversion formulas work regardless of whether R a is given in microinches (µin) or micrometers (µm). To convert metric R a to centerline average (CLA), use the following formula: CLA (µin) = R a (µm) x 40