Molecular Physics | Thermodynamics Answers

Two metal rods of same length and same cross-sectional area are coated with paraffin wax. But they are
made of different materials. K1 and K2 are thermal conductivities of 1st and 2nd rod respectively. One end
of each rod is introduced to a vapor compartment where the temperature is maintained at 100o
C and the
other end is kept at lower room temperature. After some time it is found that wax of 1st rod has melted
over 50cm and wax of the 2nd one has melted over 25cm. Find a relation between K1 and K2.

A simple pendulum with a length of 2.23m and a mass of 6.74kg is given an initial speed of 2.06m/s at its equilibrium position. Assume it undergoes simple harmonic motion, and determine its (a) period (b) total energy (c) maximum angular displacement.

A 1.5 kW hotplate is used to heat 250ml of water in a 292.1g glass beaker both the water and the glass beaker are initially at 20.5C the hotplate is used for 5.5 minutes and produces 495kJ of energy when used. Determine the final temperature of the glass beaker

What is the mass of 750 liters of gasoline?
( Take Pgasoline = 680kg/m cube

A hydraulic jack system is created in the configuration below. A person pushes down with force F on one end of the lever arm of total length l= 1.2m. The lever arm is attached to a fixed pivot on the opposite end and in turn pushes straight down on the input piston, located halfway down the lever arm, with Fi. The ratio of the output pistons area to the input pistons area is Ao/Ai=55. You want the output force to sustain the weight of a W = 6000N object.
a) Algebraically find the input pistons force Fi in terms of the persons force F using a torque argument.
b) Find the required force the person must exert in order to support the object by relating the expression for Fi to Fo.

The Westin Stamford Hotel in Detroit is 228 m tall. Suppose a piece of ice, which initially has a temperature of 0.0 C, falls from the hotel roof and crashes to the ground. Assuming that 50.0 percent of the ice's mechanical energy during the fall and collision is absorbed by the ice and that 3.33*10^5 J is required to melt 1.00 kg of ice, calculate the fraction of the ice's mass that would melt.

a gas expands from 5 litre to 105 litre at a constant pressure 100n/m2 the work done is

A glass laboratory flask is filled with gas at 27∘C and 0.97atm pressure, sealed, and then heated to 139∘C. What is the pressure inside the flask?

A copper cup holds some cold water at 4 C. The copper cup weighs 140g while the water weighs 80g. If 100g of hot water, at 90 C is added, what will be the final temperature of the water?

work done in converting one gram of ice at -10 degree c into steam at 100 degree c is