Question

Berapakah koefisien viskositas cairan tersebut!

buat besok tolong di bantu

Answer 1

dik.

D = 11,4 mm

mk = 2,15 gr

Vx = 50 ml

mx = 37 gr

d= 36 cm

t = 0,8 s

Dit. viskositas η

Jawab

Volume kelereng

Vk = 4/3. π.r³

Vk = 4/3.π.(5,7.10⁻³)³

Vk = 775.73.10⁻⁹ m³

massa jenis kelereng

ρk = mk/Vk = 2,15.10⁻³/(775.73.10⁻⁹)

ρk = 0.00277.10⁶

ρk = 2,77.10³ kg/m³

massa jenis cairan

ρx = mx/Vx = 37/50 gr/ml

ρx = 0,74. 10⁻³/10⁻⁶ kg/m³

ρx = 0,74.10³ kg/m³

kecepatan kelereng

v = d/t = 36.10⁻²/0,8

v = 0,45 m/s

kelereng berat w bergerak ke bawah mendapat gaya apung dan gaya viskositas keatas

Fa + Fv - W = 0

ρx.Vk.g + 6πηrv - ρk.Vk.g = 0

Vk.g(ρx - ρk) + 6πηrv = 0

η = -Vk.g(ρx - ρk)/(6πrv)

η = -775.73.10⁻⁹. 10.(0,74.10³ - 2,77.10³)/(6π.5,7.10⁻³.0,45)

η = 0.0157/0.0483

η = 0,325 Ns/m²

Koefisien viskositas cairan ini 0,325 N.s/m²