The cylindrical tube of a spray pump has a cross-section of 8.0 cm2 one end of which has 40 fine holes each of diameter 1.0 mm. If the liquid flow inside the tube is `1.5 m min-^1`, what is the speed of ejection of the liquid through the holes?

A ‘thermacole’ icebox is a cheap and efficient method for storing small quantities of cooked food in summer in particular. A cubical icebox of side 30 cm has a thickness of 5.0 cm. if 4.0 kg of ice is put in the box, estimate the amount of-ice remaining after 6 h. The outside temperature is 45 ^@C , and co-efficient of thermal conductivity of thermacole is 0.01 J s^-1.m-^1 K-^1 . [Heat of fusion of water = 335 x 103 J kg^-1

Water is flowing steadily through a horizontal pipe of non- uniform cross-section. The pressure of water is 4xx10^4 at a point, where cross-section is 0.02m^2 and velocity of flow is 2ms^-1 . What is the pressure at a point, where cross-section reduces to 0.01m^2 ?

A brass sheet has a circular hole of diameter 3 cm at 30°C .What will be the change in diameter of the hole when it is heated to 120°C ?Given alpha_brass= 2 *10^ -5°C^-1 .

Water flows horizontally through a pipeline of varying cross-section. At two points A and B, the diameters are 0.6 m and 0.2m. The pressure difference between the points is 1m. Column of water. Calculate the volume of water flowing per second.

Mercury has an angle of contact equal to 140^@ with soda lime glass. A narrow tube of radius 1.00 mm made of this glass is dipped in a trough containing mefcury. By what amount does the mercury dip down in the tube relative to the liquid surface outside? Surface tension of mercury at the temperature of the experiment is 0.465 N m^-1 . Density of mercury = 13.6 xx 10^3 kg m^-3

A-stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m with a speed of 40 rev./min in a horizontal plane. What is the tension in the string? What is the maximum speed with which the stone can be whirled around if the string can withstand a maximum tension of 200. N?

A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km h ^-1 . Finding the market closed, he instantly turns and walks back home with a speed of 7.5 km h^-1 . What is the average speed of the man over the interval of time (i) 0 to 30 min, (ii) 0 to 50 min, (Hi) 0 to 40. min? [Note: You will appreciate from this exercise why . it is better to define average speed as total path length divided by time, and not as magnitude of average velocity. You would not like to tell the tired man on his return home that his average speed was zero!]

A sonometer wire is under tension of 40 N and the length between the two bridges is 60 cm.A one metre long wire of the sonometer has a mass of 1.0 g.Deduce the speed of transverse waves and the frequency of the second harmonic.