--%>
Assignment Help - homework help

Problem on melting of ice

A) It has been suggested that the surface melting of ice plays a role in enabling speed skaters to achieve peak performance. Carry out the following calculation to test this hypothesis. Suppose that the width of the skate in contact with the ice has been reduced by sharpening to 0.25 mm. and that the length of the contact area is 15 cm.

i) If a skater of mass 85 kg is balanced on one skate, what pressure (in bar) is exerted at the interface of the skate and ice?

ii) If the temperature of the ice is -5.0°C, do you expect melting of the ice at the ice-skate interface to occur? Why?

B) At what temperature does water boil on the top of Mount Everest, the elevation h = 8848m? Use only the following information to obtain your estimate:

-Dependence of pressure with the altitude is given by

P = Patm exp [(-MWgh)/RT]

where, Patm is atmospheric pressure, g is the gravitational acceleration, MW is the molecular weight of air and T is average temperature (=273 K).

-Normal boiling point (B.P.) of water is 100°C.

-The latent heat of vaporization of the water is 2257 KJ/Kg.

   Related Questions in Chemistry

  • Q : Homework Silicon has three naturally

    Silicon has three naturally occurring isotopes. 28Si, mass = 27.976927; 29Si, mass = 28.976495; 30Si, mass = 29.973770 and 3.10% abundance. What is the abundance of 28Si?

    		•
  • Q : What is Spectroscopy? This is a very

    This is a very important aspect of Physical Chemistry in which knowledge of the size, shape, rigidity and electronic structure of molecules deduced from the experimental methods treated here goes hand in hand with the theoretical approaches of chemical reactions. Spec

    		•
  • Q : Explain the mechanism of Enzyme

    A mechanism for enzyme-catalyzed reactions that leads to the typical rate equation for these reactions can be described.A variety of rate equations are required to portray the rates of enzymes catalyzed reagents and physical conditions that are encountered

    		•
  • Q : What is Henry law constant and its

    1. The units of Henry Law constant are same as those of pressure, i.e. torr or h bar. 2. Different gases have dissimilar values of Henry law constant. The values of KH for some gases in water are given in tabl

    		•
  • Q : Problem on reversible and irreversible

    The second law states that  dS ≥ (dQ/T), where dS = dQ/T for a reversible process and dS > dQ/T for an irreversible process.   a. Show that since dW12 = -dW21 (dWreverse = -dWforward) for a r

    		•
  • Q : What are different mechanisms for

    Nucleophilic substitution reactions in halides containing  - X bond may take place through either of the two different mechanisms,S<

    		•
  • Q : What are halogen oxoacids? Fluorine

    Fluorine yields only one oxyacid, hypo

    		•
  • Q : Pressure and power for adiabatic

    a) Air flowing at 1 m3/s enters an adiabatic compressor at 20°C and 1 bar. It exits at 200°C. The isentropic efficiency of the compressor is 80%. Calculate the exit pressure and the power required. b) Steam enter

    		•
  • Q : Which solution will have highest

    Which solution will have highest boiling point:(a) 1% solution of glucose in water  (b) 1% solution of sodium chloride in water  (c) 1% solution of zinc sulphate in water  (d) 1% solution of urea in waterAnswer: (b) Na

    		•
  • Q : Theory of one dimensional motion For

    For motion in one dimension, the distribution of the molecules over quantum states, speeds, and energies can be deduced.Here we show that the energy of a macroscopic gas sample can be described on the basis of our knowledge of the quantum states allowed to

    		•