What is the unit measure of heat and what causes capillarity?

1. The unit measure of heat is energy. The standard unit for energy is the Joule (J), and Kilojoule (Kj) is a common multiple.

• A. Kj
• B. KN/m² (unit of pressure)
• C. °C (unit of temperature)
• D. m³ (unit of volume)

The correct option is A.

$$\boxed{\text{A. Kj}}$$

2. Capillarity is the movement of a liquid through narrow spaces against the force of gravity. This phenomenon is caused by the combined effects of cohesive forces (attraction between liquid molecules) and adhesive forces (attraction between liquid molecules and the surface of the narrow space).

• A. Compression
• B. Cohesion and adhesion force
• C. Temperature
• D. Atmospheric pressure

The correct option is B.

$$\boxed{\text{B. Cohesion and adhesion force}}$$

3. A wide range of pipes available on the market today are manufactured from various materials. Plastic pipes (e.g., PVC, PEX) are widely used due to their versatility, cost-effectiveness, and resistance to corrosion, making them a very common choice for a wide range of applications.

• A. Copper
• B. Fibres
• C. Cast iron
• D. plastic

The correct option is D.

$$\boxed{\text{D. plastic}}$$

4. In a drainage system, a trap is a U-shaped or S-shaped pipe fitting that holds a small amount of water. This water creates a seal that prevents foul-smelling sewer gases from flowing back from the drainage system into the building.

• A. Stop cork
• B. Valve key
• C. A trap
• D. A grating

The correct option is C.

$$\boxed{\text{C. A trap}}$$

5. Electrolytic corrosion, also known as galvanic corrosion, occurs when two different types of metals are in electrical contact with each other and are both exposed to an electrolyte (an electrically conductive solution). This creates an electrochemical cell where one metal corrodes preferentially.

• A. Different type of metal in contact in presence of electrolyte
• B. Metals which are exposed in atmospheric condition
• C. Non-ferrous metal
• D. Ferrous metal

The correct option is A.

$$\boxed{\text{A. Different type of metal in contact in presence of electrolyte}}$$