IB HSC Thermal Physics

A tutorial sheet of true-false questions on thermal physics concepts is given below.

1. Particles of an ideal gas do not collide with each other.
2. Particles of an ideal gas all have the same speed.
3. The ideal gas approximation works best at high temperatures and pressures.
4. The pressure exerted by a gas is due to the momentum of the particles.
5. No heat energy flows between two objects at the same temperature.
6. A large mass at a low temperature has the same amount of heat energy as a smaller mass at a higher temperature.
7. To find the Kelvin temperature we add 273.16 to the celsius temperature.
8. An object of higher specific heat capacity takes a longer time interval to undergo a given temperature change than one of lower specific heat capacity.
9. Heat energy is the amount of energy a substance possesses.
10. The SI unit for thermal conductivity is the Jm^-2s^-1K^-1
11. A flat sheet of iron of mass m is left in the Sun and its temperature changes by T. If a flat sheet of iron of mass 2m is left in the Sun for the same time interval its temperature change is T/2.

IB HSC Physics Coulomb's Law

A tutorial sheet of harder problems on Coulomb’s law is given below.

1. Point charges +4Q and -Q are placed a distance d apart in a vacuum. Where is the resultant electric field zero?
2. Draw the electric field lines around the charges in question 1.
3. Two point charges +4Q and +Q are placed a distance d apart in a vacuum. Where is the resultant electric field zero?
4. Draw the electric field lines around the charges in question 3.
5. Three equal point charges +Q are placed at the vertices of an equilateral triangle of side d. Is the resultant electric field ever zero?
6. Draw the electric field lines around the charges in question 5.
7. Four equal point charges +Q are placed at the corners of a square of side d. Is the resultant electric field ever zero?
8. Draw the electric field lines around the charges in question 7.
9. Four equal point charges +Q are placed at the corners of a regular tetrahedron of side d. Calculate the magnitude of the resultant force acting on one of the charges. [F√6, where F is the force between two of the charges]
10. Eight equal point charges +Q are placed at the corners of a cube of side d. Is the resultant electric field zero at the centre of the cube?
11. *In question 10 what is the magnitude of the resulant electric field at a small distance from the centre of the cube?