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Physics Measurements

Physics, because it is a quantitative science, requires several measurements taken during experiments. Measurements are the assignment of numbers to objects or events. It is a cornerstone of most natural sciences, technology, economics, and quantitative research in other social sciences. It is important to be versed on the different units and recorded measurement techniques to ensure the answers are being recorded correctly.

Any measurement can be judged by the following meta-measurement criteria values, level of measurement, dimensions and uncertainty. These enable comparisons to be done between different measurements and reduce confusion. Increased precision through quantitative measurements is often preferred in cases of clear qualitative similarities of differences in order to aid in replication.

Measurements must be carried out with computational operations using the same units and conversion factors. It is also important to be aware of scalar and vector operations in detailed calculations. It is easy to be off by a multiplication factor in a mathematically heavy calculation which requires a detailed understanding in conversations and units. 

Categories within Physics Measurements

Accuracy & Precision

Postings: 7

The measurement of the degree of closeness or reproducibility of results.

Drawing Graphs

Postings: 11

Graphs are pictorial representations of numerical data.

Units

Postings: 56

Units are used to measure and describe quantitative data.

Vector and Acceleration

** Please see the attached file for the complete problem description ** Velocity and acceleration: consider a velocity vector given in standard unit vector form in rectangular Cartesian coordinates as ____ (please see the attached file). a. What is the acceleration at 2 seconds? b. What is the displacement at 5 seconds? c.

Spin 1/2 System: Pure and Mixed Ensembles

Consider a pure ensemble of a spin 1/2 system. Suppose <Sx>, <Sz> and the sign of <Sy> are known. Show how we may determine the state vector. Why is it unnecessary to know the magnitude of <Sy> ? Consider a mixed ensemble of a spin 1/2 system. Suppose [Sx], [Sy] and [Sz] are known. Show how we may construct the 2x2 densi

Tensor Products observables.

In the Hilbert space C^2 x C^2 (where x is used in all of my notation to mean the cross product) Consider the state vector: Psi = 1/sqrt(2) ( e_1 X e_2) + 1/sqrt(2) ( e_2 X e_1 ) (Part a) What is the probability that the measurement of q_3 X I gives the value -1 and how does the state vector change in

Buoyancy and Archmides Principle

Would you explain how to solve the following problem to the specified answer of 0.199? Please offer as much explanation as possible. What fraction of a piece of aluminum will be submerged when it floats in mercury?

Understanding the Prefix

Question: What is the correct prefix to the fun-word "103-mockingbird". a. deci b. tera c. peta d. pico e. kilo

Pressure Measurements

A piston (1) as shown in the figure has a diameter of 0.25 inches, and piston (2) has a diameter of 1.5 inches. In the absence of friction, determine the force F necessary to support the 500-lb weight.

Pascal's Principle and Blood Pressure Measuring

When a person's blood pressure is taken, it is measured on the arm, at approximately the same level as the heart. How would the results differ if the measurement were to be made on the patient's leg? Would the pressure be greater, according to the P2 = P2 + pgh equation? Thank you!