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
Δp = 600 kPaPQ = 100 L/s

A pump raises the pressure of 100 L/s of water by 600 kPa. Inlet and outlet are at the same height and have the same diameter. Find the hydraulic power Ph in kW.

Q = 100 L/sΔp = 600 kPa
Ph = kW
2.Easy
PQ = 12 L/sH = 73 m

A pump delivers 12 L/s of water (ρ = 1000 kg/m³) against a total head of 73 m. Use g = 9.81 m/s². Find the hydraulic power Ph given to the water, in kW.

Q = 12 L/sH = 73 mρ = 1000 kg/m³g = 9.81 m/s²
Ph = kW
3.Medium
PQ = 50 L/sH = 78 m

In a test, a pump delivers 50 L/s of water (ρ = 1000 kg/m³) against a head of 78 m while its shaft takes 51 kW. Use g = 9.81 m/s². Find the pump efficiency η in percent.

Q = 50 L/sH = 78 mPshaft = 51 kWg = 9.81 m/s²
η = %
4.Medium
PQ = 25 L/sH = 30 m

In a test, a pump delivers 25 L/s of water (ρ = 1000 kg/m³) against a head of 30 m while its shaft takes 8.7 kW. Use g = 9.81 m/s². Find the pump efficiency η in percent.

Q = 25 L/sH = 30 mPshaft = 8.7 kWg = 9.81 m/s²
η = %
5.Hard
150 kPa (gauge)PQ = 60 L/sΔz = 7 mL = 150 m, D = 200 mm, f = 0.02, ΣK = 6

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 7 m higher. The pipe is 150 m long with an inside diameter of 200 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 150 kPa. Find the head H the pump must add.

Q = 60 L/sΔz = 7 mL = 150 mD = 200 mmf = 0.02ΣK = 6ptank = 150 kPa
H = m
6.Hard
PQ = 50 L/sΔz = 34 mL = 100 m, D = 150 mm, f = 0.022, ΣK = 8

A pump moves 50 L/s of water (ρ = 1000 kg/m³) from an open lower reservoir to an upper tank whose water surface is 34 m higher. The pipe is 100 m long with an inside diameter of 150 mm and a Darcy friction factor f = 0.022; the minor-loss coefficients add up to ΣK = 8 (entrance and exit included). Use g = 9.81 m/s². Find the head H the pump must add.

Q = 50 L/sΔz = 34 mL = 100 mD = 150 mmf = 0.022ΣK = 8
H = m

Answer key

  1. 1. Ph = 60 kW
  2. 2. Ph = 8.594 kW
  3. 3. η = 75.02 %
  4. 4. η = 84.57 %
  5. 5. H = 26.19 m
  6. 6. H = 43.25 m

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