Wheatstone bridge & strain gauges worksheet with answers

Free printable Wheatstone bridge & strain gauges worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheet Practise 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

Find the open-circuit output voltage V_ab = V_a − V_b of the bridge shown, with V_s = 15 V.

V_s = 15 VR₁ = 100 ΩR₂ = 800 ΩR₃ = 1000 ΩR₄ = 300 Ω

V_ab = V

2.Easy

In the bridge shown, V_s = 3 V, R₁ = 1000 Ω and R₂ = 120 Ω. Find the voltage V_a of node a with respect to the negative supply rail.

V_s = 3 VR₁ = 1000 ΩR₂ = 120 ΩR₃ = 10 ΩR₄ = 800 Ω

V_a = V

3.Medium

A bridge has four 220 Ω arms and V_s = 10 V. The sensor R₂ increases by ΔR = 33 Ω. Find the exact output V_ab in mV.

V_s = 10 VR = 220 ΩΔR = 33 Ω

V_ab = mV

4.Medium

A bridge with four 300 Ω arms is supplied with 6 V. When the sensor R₂ changes, the output reads V_ab = 73.17 mV. Find the exact change ΔR of R₂.

V_s = 6 VR = 300 ΩV_ab = 73.17 mV

ΔR = Ω

5.Hard

A quarter bridge (one active gauge, GF = 2.05) is excited with 2.5 V. The largest strain to be measured is 600 µε, and it must give 10 V at the input of an analogue-to-digital converter. Find the amplifier gain G.

V_s = 2.5 VGF = 2.05ε_max = 600 µεV_FS = 10 V

G =

6.Hard

A bridge with 120 Ω arms is excited with 5 V and has two active gauges in adjacent arms, one in tension and one in compression (half bridge). The gauge factor is 2 and the strain is 200 µε. Find the bridge output V_o in mV.

V_s = 5 VGF = 2ε = 200 µε

V_o = mV

Answer key

1. V_ab = 9.872 V
2. V_a = 0.3214 V
3. V_ab = 348.8 mV
4. ΔR = 15 Ω
5. G = 13008
6. V_o = 1 mV

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