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 = 12 L/sH = 26 m

A pump delivers 12 L/s of water (ρ = 1000 kg/m³) against a total head of 26 m. Use g = 9.81 m/s². Find the hydraulic power Ph given to the water, in kW.

Q = 12 L/sH = 26 mρ = 1000 kg/m³g = 9.81 m/s²
Ph = kW
3.Medium
PQ = 150 L/sH = 56 m

In a test, a pump delivers 150 L/s of water (ρ = 1000 kg/m³) against a head of 56 m while its shaft takes 109.9 kW. Use g = 9.81 m/s². Find the pump efficiency η in percent.

Q = 150 L/sH = 56 mPshaft = 109.9 kWg = 9.81 m/s²
η = %
4.Medium
PQ = 25 L/sH = 16 m

In a test, a pump delivers 25 L/s of water (ρ = 1000 kg/m³) against a head of 16 m while its shaft takes 4.6 kW. Use g = 9.81 m/s². Find the pump efficiency η in percent.

Q = 25 L/sH = 16 mPshaft = 4.6 kWg = 9.81 m/s²
η = %
5.Hard
300 kPa (gauge)PQ = 25 L/sΔz = 7 mL = 100 m, D = 150 mm, f = 0.02, ΣK = 6

A pump moves 25 L/s of water (ρ = 1000 kg/m³) from an open lower reservoir to an upper tank whose water surface is 7 m higher. The pipe is 100 m long with an inside diameter of 150 mm and a Darcy friction factor f = 0.02; the minor-loss coefficients add up to ΣK = 6 (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 300 kPa. Find the head H the pump must add.

Q = 25 L/sΔz = 7 mL = 100 mD = 150 mmf = 0.02ΣK = 6ptank = 300 kPa
H = m
6.Hard
PQ = 40 L/sΔz = 7 mL = 100 m, D = 200 mm, f = 0.015, ΣK = 8

A pump moves 40 L/s of water (ρ = 1000 kg/m³) from an open lower reservoir to an upper tank whose water surface is 7 m higher. The pipe is 100 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 = 8 (entrance and exit included). Use g = 9.81 m/s². The pump efficiency is 65%. Find the shaft power Pshaft in kW.

Q = 40 L/sΔz = 7 mL = 100 mD = 200 mmf = 0.015ΣK = 8η = 65%
Pshaft = kW

Answer key

  1. 1. H = 20.39 m
  2. 2. Ph = 3.061 kW
  3. 3. η = 74.98 %
  4. 4. η = 85.3 %
  5. 5. H = 39.55 m
  6. 6. Pshaft = 4.999 kW

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