Figure 10.24 (a) shows a thin liquid film supporting a small weight = `4.5xx 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 1.5xx 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 ?

In the above problem, If the yield strength of steel is 2.5 xx 10^8 N m^-2 , what is the maximum weight that can be hung at the lower end of the wire?

A steel tape 1 metre long is correctly calibrated for temperature of 27.0^@C . The length of a steel rod measured by this tape is found to be 63.0 cm on a h ot day when the temperature is 45^@C . What is the actual length of the steel rod on that day? What is the length of the same steel rod on a day when the temperature is 27.0^@C ? Coefficient of linear expansion of steel = 1.20 xx 10^-5 C^-1 .

The Sun is a hot plasma (ionized matter) with its inner core at a temperature exceeding 107 K, and its outer surface at a temperature of about 6000 K. At these high temperatures, no substance remains in a solid or liquid phase. In what range do you expect the mass density of the Sun to be, in the range of densities of solids and liquids or gases ? Check if your guess is correct from the following data : mass of the Sun = 2.0 xx 10^30 kg , radius of the Sun = 7.0 xx 10^8 m .

A sample of paramagnetic salt contains 2.0 xx 10^24 atomic dipoles each of dipole moment 1.5 xx 10^-23 JT^-1 . The sample is placed under a homogeneous magnetic field of 0.64 T, and cooled to a temperature of 4.2 K. The degree of magnetic saturation achieved is equal to 15%. What is the total dipole moment of the sample for a magnetic field of 0.98 T and a temperature of 2.8 K? (Assume Curie’s law)

The forward rate constant for the elementary reversible gaseous reaction C_(2)H_(6)ltimplies2CH_(3) "is" 1.57xx10^(-3)s^(-1)at 100 K What is the rate constant for the backward reaction at this temperature if 10^(-4) moles of CH_(3) and 10 moles of C_(2)H_(6) are present in a 10 litre vessel at equilibrium . a) 1.57xx10^(9) L "mole"^(-1)s^(-1) b) 1.57xx10^(10) L "mole"^(-1)s^(-1) c) 1.57xx10^(11) L "mole"^(-1)s^(-1) d) 1.57xx10^(7) L "mole"^(-1)s^(-1)

A farmer harvests his crop and expresses his harvest in three different ways: (a) I have harvested 10 quintals of wheat. (b)1 have harvested 10 quintals of wheat today in one acre of land. (c) I have harvested 10 quintals of wheat in one acre of land after 6 months from sowing. Do the above statements mean one and the same thing. If your answer is yes, give reasons. And if your answer is 'no' explain the meaning of each expression.

Let * be the binary operation on the set {1,2,3,4,5}, defined by a *' b = H.C.F of a and b. Is the operation *' same as the operation * defined above? Justify your answer.