A plane is in level flight at constant speed and each of its two wings has an area of 25 m². If the speed of the air is 180 km/h over the lower wing and 234 km/h over the upper wing surface, determine the plane’s mass. (Take air density to be 1 kgm–³).
(a) What is the largest average velocity of blood flow in an artery of radius 2×10–³m if the flow must remain lanimar? (b) What is the corresponding flow rate ? (Take viscosity of blood to be 2.084 × 10–³ Pa s).
In deriving Bernoulli’s equation, we equated the work done on the fluid in the tube to its change in the potential and kinetic energy.
(a) What is the largest average velocity of blood flow in an artery of diameter 2 × 10–3 m if the flow must remain laminar ?
(b) Do the dissipative forces become more important as the fluid velocity increases ? Discuss qualitatively.
During blood transfusion the needle is inserted in a vein where the gauge pressure is 2000 Pa. At what height must the blood container be placed so that blood may just enter the vein ? [Use the density of whole blood from Table 10.1].
Two vessels have the same base area but different shapes. The first vessel takes twice the volume of water that the second vessel requires to fill upto a particular common height. Is the force exerted by the water on the base of the vessel the same in the two cases ? If so, why do the vessels filled with water to that same height give different readings on a weighing scale ?
A manometer reads the pressure of a gas in an enclosure as shown in Fig. 10.25 (a)When a pump removes some of the gas, the manometer reads as in Fig. 10.25 (b)The liquid used in the manometers is mercury and the atmospheric pressure is 76cm of mercury.
(a) Give the absolute and gauge pressure of the gas in the enclosure for cases (a)
and (b), in units of cm of mercury.
(b) How would the levels change in case (b) if 13.6 cm of water (immiscible with
mercury) are poured into the right limb of the manometer ? (Ignore the small
change in the volume of the gas).
What is the excess pressure inside a bubble of soap solution of radius 5.00 mm, given that the surface tension of soap solution at the temperature (20 °C) is 2.50 ×10–² N m–¹ ? If an air bubble of the same dimension were formed at depth of 40.0cm inside a container containing the soap solution (of relative density 1.20), what would be the pressure inside the bubble ? (1 atmospheric pressure is 1.01 × 10⁵ Pa).
What is the pressure inside the drop of mercury of radius 3.00 mm at room temperature ? Surface tension of mercury at that temperature (20 °C) is 4.65 ×10–¹ N m–¹. The atmospheric pressure is 1.01 × 10⁵ Pa. Also give the excess pressure inside the drop.
Figure 10.24 (a) shows a thin liquid film supporting a small weight = 4.5 × 10–2 N. What is the weight supported by a film of the same liquid at the same temperature in Fig. (b) and (c) ? Explain your answer physically.
A U-shaped wire is dipped in a soap solution, and removed. The thin soap film
formed between the wire and the light slider supports a weight of 1.5 × 10–² N
(which includes the small weight of the slider). The length of the slider is 30 cm.
What is the surface tension of the film ?
+91 94284 01196 (WhatsApp only)
C-15, Suvidhapark Society, Amitnagar circle, Karelibaug, Vadodara (390018)
© Copyright 2025. Doubtora. All Rights Reserved
