(a)(i)
For the correct answer: The liquid rises/expands.
When the temperature increases, the liquid particles gain kinetic energy and move more vigorously. This leads to an increase in the average separation between the particles, causing the liquid to expand and rise up the narrow bore of the thermometer tube.
(a)(ii)
For the correct answer: $291\text{ K}$
To convert a temperature from degrees Celsius to the absolute Kelvin scale, add $273$ to the Celsius value. Following the formula $T\text{ (in K)} = \theta\text{ (in °C)} + 273$, the calculation is $18 + 273 = 291\text{ K}$.
(b)
For the correct answer: Pressure decreases.
As the temperature drops, gas particles lose kinetic energy and move more slowly. This results in less frequent and less forceful collisions between the particles and the internal walls of the metal can, thereby reducing the outward pressure exerted by the air.
(c)
For the correct answer: $836.4\text{ N}$
Pressure is defined as the force acting per unit area, expressed by the equation $p = F / A$. By rearranging this to solve for force ($F = p \times A$), we multiply the pressure of $102,000\text{ N/m}^2$ by the area of $0.0082\text{ m}^2$ to find the total force of $836.4\text{ N}$.
