Master Plumbing Basics: Water Pressure, Flow Rates, and Drainage Systems

Question 1

What is the typical flow rate for a bathroom faucet?

Accepted Answer

1-4 gallons per minute (GPM)

Answer

5-8 GPM

Answer

10-15 GPM

Answer

20-25 GPM

Question 2

Which drainage system is typically used in residential buildings?

Accepted Answer

Sanitary drainage system

Answer

Storm drainage system

Answer

Combined drainage system

Answer

Food waste drainage system

Question 3

What is the minimum recommended slope for a drainage pipe?

Accepted Answer

1/4 inch per foot

Answer

1/2 inch per foot

Answer

3/4 inch per foot

Answer

1 inch per foot

Question 4

Which material is commonly used for hot water pipes due to its durability and heat resistance?

Accepted Answer

Copper

Answer

Polyvinyl chloride (PVC)

Answer

Cast iron

Answer

Galvanized steel

Question 5

What is the main function of a pressure-reducing valve in a plumbing system?

Accepted Answer

To reduce incoming water pressure to a safe level

Answer

To increase incoming water pressure to improve flow rates

Answer

To prevent leaks and ruptures in the plumbing system

Answer

To regulate the temperature of incoming water

Question 6

Which type of joint is specifically designed for connecting copper pipes?

Accepted Answer

Soldered joint

Answer

Threaded joint

Answer

Compression joint

Answer

Flared joint

Question 7

Which tool is used to cut and shape PVC pipes?

Accepted Answer

Pipe cutter

Answer

Hacksaw

Answer

Circular saw

Answer

Miter saw

Question 8

Which type of drain fitting connects a sink or bathtub to a drain pipe?

Accepted Answer

P-trap

Answer

S-trap

Answer

Floor drain

Answer

Cleanout plug

Question 9

What is the main purpose of a float valve in a toilet tank?

Accepted Answer

To control the water level

Answer

To flush the toilet

Answer

To regulate water pressure

Answer

To prevent water leaks

Question 10

What is the minimum pipe size allowed for a drain line serving a bathroom sink?

Accepted Answer

1-1/2 inches

Answer

2 inches

Answer

2-1/2 inches

Answer

3 inches

Question 11

Which type of valve is typically used to shut off the water supply to a fixture?

Accepted Answer

Ball valve

Answer

Gate valve

Answer

Globe valve

Answer

Check valve

Question 12

What is the primary purpose of a water softener in a plumbing system?

Accepted Answer

To remove minerals from water

Answer

To increase water pressure

Answer

To prevent corrosion

Answer

To improve drainage

Question 13

The flow rate of a fixture is typically measured in:

Accepted Answer

Gallons per minute (GPM)

Answer

Gallons per hour (GPH)

Answer

Cubic feet per minute (CFM)

Answer

Cubic feet per hour (CFH)

Question 14

The purpose of a trap in a plumbing system is to:

Accepted Answer

Prevent sewer gases from entering the building

Answer

Prevent water from flowing back into the fixture

Answer

Filter out debris before it enters the drain

Answer

Provide a water seal to prevent freezing

Question 15

The temperature of water supplied to fixtures in a home should be:

Accepted Answer

120-130 degrees Fahrenheit

Answer

110-120 degrees Fahrenheit

Answer

130-140 degrees Fahrenheit

Answer

140-150 degrees Fahrenheit

Question 16

Which type of pipe fitting is used to change the direction of a pipe by 90 degrees?

Accepted Answer

Elbow

Answer

Tee

Answer

Cross

Answer

Union

Question 17

The primary function of a water heater is to:

Accepted Answer

Provide a source of hot water for fixtures

Answer

Heat water for space heating

Answer

Cool water for air conditioning

Answer

Filter water for drinking purposes

Question 18

Which of the following is a safety hazard associated with gas-fired water heaters?

Accepted Answer

Carbon monoxide poisoning

Answer

Electric shock

Answer

Scalding

Answer

Fire

Question 19

Which type of pipe is commonly used for potable water supply in residential buildings in the United States?

Accepted Answer

Copper

Answer

Galvanized steel

Answer

ABS

Answer

PVC

Question 20

What is the primary purpose of a pressure reducing valve (PRV) in a plumbing system?

Accepted Answer

To maintain safe water pressure levels by reducing excessively high pressure.

Answer

To regulate temperature.

Answer

To prevent backflow.

Answer

To increase water flow rate.

Question 21

What is the main function of a trap in a plumbing fixture?

Accepted Answer

To prevent sewer gases and pests from entering the building through drains.

Answer

To regulate water flow.

Answer

To collect and discharge wastewater.

Question 22

Which type of fitting is used for connecting pipes at an angle of 90 degrees?

Accepted Answer

Elbow

Answer

Cross

Answer

Tee

Answer

Reducer

Question 23

What is the purpose of an expansion tank in a water heater system?

Accepted Answer

To accommodate the increase in water volume due to thermal expansion and prevent pressure buildup.

Answer

To prevent leaks.

Answer

To increase water temperature.

Question 24

Which unit of measurement is used to express water pressure in the metric system?

Accepted Answer

Kilopascal (kPa)

Answer

Bar

Answer

Pound per square inch (psi)

Answer

Atmospheres (atm)

Question 25

What is the primary function of a backflow preventer in a plumbing system?

Accepted Answer

To prevent the contamination of the potable water supply by preventing the backflow of non-potable water.

Answer

To regulate water flow.

Answer

To increase water pressure.