Air is streaming past a horizontal air plane wing such that its speed in $ 120 m/s$  over the upper surface and $ 90 m/s$  at the lower surface. If the density of air is $1.3 kg$  per $metre^3 $ and the wing is $10 m $ long and has an average width of $2 m$, then the difference of the pressure on the two sides of the wing of ....... $Pascal$ 

Give reason why mercury does not wet glass.

A tube is attached as shown in closed vessel containing water. The velocity of water coming out from a small hole is :

Water flows through the tube shown. Area of cross-section of wide and narrow part are $5$ $cm^2$ $\&$ $2$ $cm^2$. The rate of flow is $500$ $cm^3/sec$. Find difference in mercury level of $U-$ tube .......... $cm$

Alaminar stream is flowing vertically down from a tap of cross-section area $1$ $cm^2$. At a distance $10 $ $cm$ below the tap, the cross-section area of the stream has reduced to $1/2$ $cm^2$. The volumetric flow rate of water from the tap must be about ........ $litre/\min$

$Assertion :$ The velocity of flow of a liquid is smaller when pressure is larger and vice-versa.
$Reason :$ According to Bernoulli’s theorem, for the stream line flow of an ideal liquid, the total energy per unit mass remains constant.