The velocity of a small ball of mass \(M\) and density \(d\), when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is \(d\over 2\) then the viscous force acting on the ball will be:
1. | \(\frac{3Mg}{2}\) | 2. | \(2Mg\) |
3. | \(\frac{Mg}{2}\) | 4. | \(Mg\) |
A barometer is constructed using a liquid (density = \(760~\text{kg/m}^3\)). What would be the height of the liquid column, when a mercury barometer reads \(76\) cm?
(density of mercury = \(13600~\text{kg/m}^3\))
1. | \(1.36\) m | 2. | \(13.6\) m |
3. | \(136\) m | 4. | \(0.76\) m |
A liquid does not wet the solid surface if the angle of contact is:
1. equal to \(45^{\circ}\)
2. equal to \(60^{\circ}\)
3. greater then \(90^{\circ}\)
4. zero
The correct statement about the variation of viscosity of fluids with an increase in temperature is:
1. | viscosity of gases decreases. |
2. | viscosity of both liquids and gases increases. |
3. | viscosity of liquids increases. |
4. | viscosity of liquids decreases. |
A fluid of density \(\rho~\)is flowing in a pipe of varying cross-sectional area as shown in the figure. Bernoulli's equation for the motion becomes:
1. \(p+\dfrac12\rho v^2+\rho gh\text{=constant}\)
2. \(p+\dfrac12\rho v^2\text{=constant}\)
3. \(\dfrac12\rho v^2+\rho gh\text{=constant}\)
4. \(p+\rho gh\text{=constant}\)
Air is pushed carefully into a soap bubble of radius \(r\) to double its radius. If the surface tension of the soap solution is \(T,\) then work done in the process is:
1. | \(12\pi r^2T\) | 2. | \(24\pi r^2T\) |
3. | \(4\pi r^2T\) | 4. | \(8\pi r^2T\) |
1. | \(A\) and \(B\) is same. | pressure on the base area of vessels
2. | \(A\) and \(B\) is not same. | pressure on the base area of vessels
3. | \(A\) and \(B\) weigh the same. | both vessels
4. | \(B\) weighs twice that of \(A\). | vessel