Molecular Physics | Thermodynamics Answers

. An ideal spring of negligible mass with force constant of 400 N/m is placed on a frictionless horizonal 

table with one end fixed at a wall next to the table. A billiard ball of mass 200 g is pushed against the 

spring, compressing the spring to some distance. After the system is released, the spring returns to 

equilibrium with the billiard ball leaving the table’s edge at 4.00 m/s and hits the floor 80 cm below. 

Using the principle of energy conservation, (a) determine the initial compression of the spring. (b) 

What is the speed of the ball when it hits the floor.

Calculate the mass of a steel plate with a specific heat capacity of 650 J/kg °C, taking into

consideration the steel plate was heated up with a cutting torch while cutting to 925 °C, and was

quenched in 25 It of water with an initial temperature of 22 °C and a specific heat capacity of

3850 J/kg °C. Both the water and the steel plate reached a final temperature of 32 °C. Here we

assume that there was no heat loss. Indicate what info was given, show all formulas and steps.

A basketball floats in a bathtub of water.

The ball has a mass of 0.5 kg and a diameter of 22 cm.

(a) What is the buoyant force?

(b) What is the volume of water displaced by the ball?

(c) What is the average density of the basketball?

You can use

g

= 9

.

8 m/s

2

.

Find the energy required to convert a 1 g cube of ice at

30°C to steam at 120°C

A basketball floats in a bathtub of water. The ball has a mass of 0.5 kg and a diameter of 22 cm.

(a) What is the buoyant force?

(b) What is the volume of water displaced by the ball?

(c) What is the average density of the basketball?

You can use g = 9.8 m/s2

.

A balloon has a volume of 25.0L on a day when the temperature is 30.0 °C. If the temperature at night falls to 10.0 °C, what will be the volume of the balloon if the pressure remains constant?

xygen ( molecular weight 32) is compressed reversibly and polytropically in a

cylinder from 1.05 bar, 15oC to 4.2bar in such a way that one- third of the work input

is rejected as heat to the cylinder walls . calculate the final temperature of the oxygen.

Assume oxygen to be aperfect gas and take Cv = 0.649kJ/kg.K

Three 45-Ω lightbulbs and three 75-Ω lightbulbs are connected in series. (a) what is the total resistance of the circuit? (b) what is their resistance if all six are wired in parallel? (c) Show the circuit illustration.

A 3.00-µF and 4.00-µF capacitor are connected in series, and this combination is connected in parallel with a 2.00-µF capacitor. (a) Show the illustration (b) What is the net capacitance?