Physics

PHY430 – Lab 1 Pre-Lab Questions 1 Topic: Measurement Objective: To enable the students to state and differentiate important concepts and terms that are useful to carry out Experiment 1 meaningfully.

After answering these questions, the students will be able to 1. differentiate between zero error and reading uncertainty (error) for a meter rule, vernier caliper and a micrometer. 2. state the significant figures of a given number and use the rules for stating the significant figures at the end of a calculation. 3. differentiate between a systematic and a random uncertainty. 4. calculate the propagation of uncertainty from several combinations of measurement that includes addition, subtraction, multiplication and power formulation. PRE-LAB QUESTIONS 1 Answer the following questions and submit your group answer to the instructor. 1. Is it possible to get an exact measurement without any uncertainty (error)? 2. What is the zero error and the reading uncertainty (error) for (a) a meter rule, (b) a vernier caliper, and (b) a micrometer? 3. State the number of significant figures for each of the following numbers (a) 17.20 (b) 0.0270 (c) 12000 (d) 3.1400 4. Perform the following calculations and give the answer with the correct significant figures. (a) 23.90  3.81 (b) 10.27  2.8 (c) 4.917  1.5  12.31 5. State two major differences between a systematic and a random error? 6. Does the laboratory balance measure weight or mass? Explain. 7. What is the function of the vernier scale on the vernier caliper? Does it extend accuracy or precision? Explain.

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PHY430 – Lab 1 8. If x = 1.52  0.01 cm and y = 3.36  0.01 cm, calculate S, D, M, R and V and their uncertainty S, D, M and V respectively. (a) S = x + y (b) D = y  x (c) M = xy (d) = (e) V = x3 9. The length of a plank is measured by using a meter rule and the value obtained is reported as 2.4 m. Why is this reading inappropriately reported?

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PHY430 – Lab 1

Experiment 1 Topic: Measurement...