A plate of area 10m^(2) is made to move horizontally with a speed of 0.5 ms^(-1) by applying a force over the surface a liquid. If the depth of the liquid is 2.5m, coefficient of viscosity of liquid is 10^(-3)Nsm^(-2), then calculate the horizontal force needed to move the plate.

A plate of area 10m^(2) is made to move horizontally with a speed of 0

1.	A plate of area 10m^(2) is made to move horizontally with a speed of 0.5 ms^(-1) by applying a force over the surface a liquid. If the depth of the liquid is 2.5m, coefficient of viscosity of liquid is 10^(-3)Nsm^(-2), then calculate the horizontal force needed to move the plate.
Answer» <html><body><p></p>Solution :Given `Deltav=0.5 <a href="https://interviewquestions.tuteehub.com/tag/ms-549331" style="font-weight:bold;" target="_blank" title="Click to know more about MS">MS</a>^(-1)` <br/> `Deltax=2.5m` <br/> velocity gradient `=(Deltav)/(Deltax)=(0.5)/(2.5)=0.2(ms^(-1))/(m)` <br/> <img src="https://d10lpgp6xz60nq.cloudfront.net/physics_images/SPH_ABT_PHY_QB_XI_C10_E04_006_S01.png" width="80%"/> <br/> We <a href="https://interviewquestions.tuteehub.com/tag/know-534065" style="font-weight:bold;" target="_blank" title="Click to know more about KNOW">KNOW</a> that \|<a href="https://interviewquestions.tuteehub.com/tag/f-455800" style="font-weight:bold;" target="_blank" title="Click to know more about F">F</a>\| `=etaA((Deltav)/(Deltax))=10^(-3) xx 10^(2) xx 10^(-2)=10^(-3)N` <br/> Hence `10^(-3)N` of force is needed to be applied, to <a href="https://interviewquestions.tuteehub.com/tag/keep-527902" style="font-weight:bold;" target="_blank" title="Click to know more about KEEP">KEEP</a> the <a href="https://interviewquestions.tuteehub.com/tag/plate-1156364" style="font-weight:bold;" target="_blank" title="Click to know more about PLATE">PLATE</a> moving.</body></html>