Pumps & pump power worksheet with answers

Free printable Pumps & pump power worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
PQ = 20 L/sH = ?

A pump delivers 20 L/s of water (ρ = 1000 kg/m³) and gives it a hydraulic power of 4 kW. Use g = 9.81 m/s². Find the head H the pump adds.

Ph = 4 kWQ = 20 L/sρ = 1000 kg/m³g = 9.81 m/s²
H = m
2.Easy
PQ = 80 L/sH = ?

A pump delivers 80 L/s of water (ρ = 1000 kg/m³) and gives it a hydraulic power of 7.5 kW. Use g = 9.81 m/s². Find the head H the pump adds.

Ph = 7.5 kWQ = 80 L/sρ = 1000 kg/m³g = 9.81 m/s²
H = m
3.Medium
PQ = 15 L/sH = 14 m

In a test, a pump delivers 15 L/s of water (ρ = 1000 kg/m³) against a head of 14 m while its shaft takes 2.7 kW. Use g = 9.81 m/s². Find the pump efficiency η in percent.

Q = 15 L/sH = 14 mPshaft = 2.7 kWg = 9.81 m/s²
η = %
4.Medium
PQ = 15 L/sH = 40 m

In a test, a pump delivers 15 L/s of water (ρ = 1000 kg/m³) against a head of 40 m while its shaft takes 7.2 kW. Use g = 9.81 m/s². Find the pump efficiency η in percent.

Q = 15 L/sH = 40 mPshaft = 7.2 kWg = 9.81 m/s²
η = %
5.Hard
PQ = 60 L/sΔz = 6 mL = 200 m, D = 200 mm, f = 0.015, ΣK = 4

A pump moves 60 L/s of water (ρ = 1000 kg/m³) from an open lower reservoir to an upper tank whose water surface is 6 m higher. The pipe is 200 m long with an inside diameter of 200 mm and a Darcy friction factor f = 0.015; the minor-loss coefficients add up to ΣK = 4 (entrance and exit included). Use g = 9.81 m/s². Find the head H the pump must add.

Q = 60 L/sΔz = 6 mL = 200 mD = 200 mmf = 0.015ΣK = 4
H = m
6.Hard
350 kPa (gauge)PQ = 120 L/sΔz = 10 mL = 100 m, D = 250 mm, f = 0.02, ΣK = 8

A pump moves 120 L/s of water (ρ = 1000 kg/m³) from an open lower reservoir to an upper tank whose water surface is 10 m higher. The pipe is 100 m long with an inside diameter of 250 mm and a Darcy friction factor f = 0.02; the minor-loss coefficients add up to ΣK = 8 (entrance and exit included). Use g = 9.81 m/s². The upper tank is closed and the air above its water is at a gauge pressure of 350 kPa. Find the head H the pump must add.

Q = 120 L/sΔz = 10 mL = 100 mD = 250 mmf = 0.02ΣK = 8ptank = 350 kPa
H = m

Answer key

  1. 1. H = 20.39 m
  2. 2. H = 9.557 m
  3. 3. η = 76.3 %
  4. 4. η = 81.75 %
  5. 5. H = 9.532 m
  6. 6. H = 50.55 m

Full step-by-step solutions: practise this topic on examproblems.com.