Two small spherical metal balls, having equal masses, are made from materials of densities \(\rho_1\) and \(\rho_2\) such that \(\rho_1=8\rho_2\)
1. | \(\dfrac{79}{72}\) | 2. | \(\dfrac{19}{36}\) |
3. | \(\dfrac{39}{72}\) | 4. | \(\dfrac{79}{36}\) |
In a U-tube, as shown in the figure, the water and oil are in the left side and right side of the tube respectively. The height of the water and oil columns are \(15~\text{cm}\) and \(20~\text{cm}\) respectively. The density of the oil is: \(\left[\text{take}~\rho_{\text{water}}= 1000~\text{kg/m}^{3}\right]\)
1. \(1200~\text{kg/m}^{3}\)
2. \(750~\text{kg/m}^{3}\)
3. \(1000~\text{kg/m}^{3}\)
4. \(1333~\text{kg/m}^{3}\)
The velocity of a small ball of mass m and density when dropped in a container filled with glycerin of density becomes constant after sometime. The viscous force acting on the ball in the final stage is:-
1.
2.
3.
4. mg
A soap bubble, having a radius of \(1~\text{mm}\), is blown from a detergent solution having a surface tension of\(2.5\times 10^{-2}~\text{N/m}\). The pressure inside the bubble equals at a point \(Z_0\) below the free surface of the water in a container. Taking \(g = 10~\text{m/s}^{2}\), the density of water \(= 10^{3}~\text{kg/m}^3\), the value of \(Z_0\) is:
A small hole of an area of cross-section \(2~\text{mm}^2\) is present near the bottom of a fully filled open tank of height \(2~\text{m}\). Taking \(g = 10~\text{m/s}^2\), the rate of flow of water through the open hole would be nearly:
1. \(6.4\times10^{-6}~\text{m}^{3}/\text{s}\)
2. \(12.6\times10^{-6}~\text{m}^{3}/\text{s}\)
3. \(8.9\times10^{-6}~\text{m}^{3}/\text{s}\)
4. \(2.23\times10^{-6}~\text{m}^{3}/\text{s}\)
1. | surface tension. |
2. | density. |
3. | angle of contact between the surface and the liquid. |
4. | viscosity. |
A certain number of spherical drops of a liquid of radius \({r}\) coalesce to form a single drop of radius \({R}\) and volume \({V}\). If \({T}\) is the surface tension of the liquid, then:
1. | energy \(= 4{VT}\left( \frac{1}{{r}} - \frac{1}{{R}}\right)\) is released. |
2. | energy \(={ 3{VT}\left( \frac{1}{{r}} + \frac{1}{{R}}\right)}\) is released. |
3. | energy \(={ 3{VT}\left( \frac{1}{{r}} - \frac{1}{{R}}\right)}\) is released. |
4. | energy is neither released nor absorbed. |
A wind with a speed of \(40\) m/s blows parallel to the roof of a house. The area of the roof is \(250\) m2. Assuming that the pressure inside the house is atmospheric pressure, the force exerted by the wind on the roof and the direction of the force will be: (\(\rho_{\text {air }}=1.2\))
1. \(4 \times 10^5\) N, downwards
2. \(4 \times 10^5\) N, upwards
3. \(2.4 \times 10^5\) N, upwards
4. \(2.4 \times 10^5\) N, downwards
The approximate depth of an ocean is \(2700~\text{m}\). The compressibility of water is \(45.4\times10^{-11}~\text{Pa}^{-1}\) and the density of water is \(10^{3}~\text{kg/m}^3\). What fractional compression of water will be obtained at the bottom of the ocean?
1. \(0.8\times 10^{-2}\)
2. \(1.0\times 10^{-2}\)
3. \(1.2\times 10^{-2}\)
4. \(1.4\times 10^{-2}\)
The heart of a man pumps \(5~\text{L}\) of blood through the arteries per minute at a pressure of \(150~\text{mm}\) of mercury. If the density of mercury is \(13.6\times10^{3}~\text{kg/m}^{3}\) \(g = 10~\text{m/s}^2\), then the power of the heart in watt is:
1. \(1.70\)
2. \(2.35\)
3. \(3.0\)
4. \(1.50\)