p.1
Measurement and Units in Physics
What is a 'unit' in measurement?
The quantity used as the standard of measurement.
p.1
SI Units and Their Significance
What is the significance of SI base units?
They are defined standards for measuring physical quantities.
p.1
SI Units and Their Significance
What is the purpose of metric prefixes in SI units?
To express quantities in larger or smaller terms.
p.1
Unit Conversion and Dimensional Analysis
What is dimensional analysis?
The use of unit conversion in solving problems.
p.2
Basic and Derived Physical Quantities
What is a physical quantity?
A quantifiable or assignable property ascribed to a particular phenomenon or body.
p.2
Measurement and Units in Physics
What is measurement?
The act of comparing a physical quantity with a certain standard.
p.2
Basic and Derived Physical Quantities
What are Basic Physical Quantities?
Quantities that cannot be expressed in terms of any other physical quantity, such as length, mass, and time.
p.2
Basic and Derived Physical Quantities
What are Derived Physical Quantities?
Quantities that can be expressed in terms of fundamental quantities, such as area, volume, and density.
p.2
Definition and Importance of Physics
Why is it important to give numerical values for physical quantities?
It allows us to understand nature much more deeply than qualitative descriptions alone.
p.2
Basic and Derived Physical Quantities
How can physical quantities be defined?
By specifying how they are measured or by stating how they are calculated from other measurements.
p.2
Basic and Derived Physical Quantities
What is average speed defined as?
The total distance traveled divided by the time of travel.
p.2
Basic and Derived Physical Quantities
How many basic physical quantities can express all physical quantities?
Seven basic physical quantities.
p.3
Measurement and Units in Physics
What are measurements of physical quantities expressed in?
Units, which are standardized values.
p.3
Measurement and Units in Physics
Why are standardized units important for scientists?
They allow for meaningful expression and comparison of measured values.
p.1
Uncertainty in Measurement and Error Analysis
What is the relationship between uncertainty and significant figures?
Uncertainty is related to the number of significant figures in a number.
p.1
Definition and Importance of Physics
What is the origin of the word 'physics'?
It comes from the Greek word meaning 'nature'.
p.1
Definition and Importance of Physics
How is physics treated in relation to science?
As the base for science with various applications for ease of life.
p.1
Definition and Importance of Physics
What does physics deal with?
Matter in relation to energy and the accurate measurement of natural phenomena.
p.1
Measurement and Units in Physics
What is measurement in physics?
The comparison of an unknown quantity with a known fixed quantity.
p.5
Uncertainty in Measurement and Error Analysis
What causes systematic errors?
Measuring devices being out of calibration.
p.4
Unit Conversion and Dimensional Analysis
What is the weight of a Honda Fit in kilograms?
2,500 lb = 2,500 x 0.4536 kg = 1134.0 kg.
p.4
Uncertainty in Measurement and Error Analysis
Can measurements of physical quantities be entirely accurate?
No, all measurements have some degree of uncertainty.
p.5
Uncertainty in Measurement and Error Analysis
What are random errors a result of?
Fluctuation of measurements of the same quantity about the average.
p.5
Uncertainty in Measurement and Error Analysis
What is a common rule of thumb for determining uncertainty in a scale measuring device?
Uncertainty is equal to the smallest increment divided by 2.
p.3
SI Units and Their Significance
When was the SI system finally agreed upon?
At the eleventh International Conference of Weights and Measures in 1960.
p.3
Unit Conversion and Dimensional Analysis
How can you convert a quantity from one unit to another?
By multiplying by conversion factors.
p.5
Uncertainty in Measurement and Error Analysis
What does uncertainty characterize in measurements?
The spread of measurement results.
p.8
Scalars and Vectors: Definitions and Differences
What are some examples of scalars?
Mass, time, volume, speed.
p.8
Scalars and Vectors: Definitions and Differences
What are some examples of vectors?
Displacement, velocity, acceleration, momentum.
p.13
Basic and Derived Physical Quantities
What is a physical quantity?
A property of an object that can be quantified.
p.14
Scalars and Vectors: Definitions and Differences
In which direction is vector ⃗⃗ directed?
Along the negative x-axis.
p.13
Scalars and Vectors: Definitions and Differences
What is a scalar?
A quantity specified by a number and its unit, having magnitude but no direction.
p.5
Uncertainty in Measurement and Error Analysis
What are the two categories of errors in measurements?
Systematic Error and Random Errors.
p.12
Unit Vectors and Their Applications
How is a unit vector in the same direction as a vector defined?
It is the vector divided by its magnitude.
p.12
Scalars and Vectors: Definitions and Differences
What is the notation used for unit vectors in three dimensions?
î for x, ĵ for y, and k̂ for z.
p.9
Vector Representation and Addition Methods
What is a resultant vector?
A single vector obtained by adding two or more vectors.
p.9
Vector Representation and Addition Methods
How can vectors be added graphically?
By joining their head to tail in any order.
p.9
Vector Representation and Addition Methods
What are the components of a resultant vector?
The original vectors that are added to obtain the resultant.
p.11
Unit Vectors and Their Applications
What is a unit vector?
A vector that has a magnitude of one and is dimensionless, used to indicate direction.
p.4
Unit Conversion and Dimensional Analysis
What is the average body temperature of a house cat in Celsius if it is 101.5°F?
To convert, use the appropriate conversion formula.
p.6
Significant Figures and Their Rules
What do significant digits imply in a measurement?
They imply the error in the measurement.
p.8
Vector Representation and Addition Methods
How are vectors represented algebraically?
By a letter or symbol with an arrow over its head.
p.7
Significant Figures and Their Rules
What is Rule 1 for significant digits when multiplying or dividing?
The number of significant digits in the final answer is the same as the least accurate factor.
p.8
Scalars and Vectors: Definitions and Differences
What is the result of multiplying a vector by a scalar?
The new vector becomes a different physical quantity.
p.13
Basic and Derived Physical Quantities
What are derived quantities?
Quantities that can be expressed in terms of fundamental quantities, such as area, volume, and density.
p.14
Scalars and Vectors: Definitions and Differences
What is the result of vector addition or subtraction dependent on?
The direction and magnitude of the vectors involved.
p.3
SI Units and Their Significance
What does SI stand for?
International System of Units.
p.3
SI Units and Their Significance
What is the primary purpose of the SI system?
To serve as the primary system of units of measurement worldwide.
p.4
Unit Conversion and Dimensional Analysis
What is the speed limit of 30 km/hr in miles per hour?
To convert, use the appropriate conversion factor.
p.5
Uncertainty in Measurement and Error Analysis
How can systematic errors be eliminated?
By pre-calibrating against a known, trusted standard.
p.5
Uncertainty in Measurement and Error Analysis
Why is it essential for science students to learn about uncertainties?
Because physics involves a lot of measurements and calculations with uncertainties.
p.10
Vector Representation and Addition Methods
How can a three-dimensional vector A be expressed?
As the sum of its x, y, and z components: A = Ax + Ay + Az.
p.7
Significant Figures and Their Rules
Why is the number 300 not well defined in terms of significant figures?
Because it can represent different levels of precision; it should be expressed in scientific notation.
p.14
Vector Representation and Addition Methods
How do you find the magnitude of the vector sum ⃗ + ⃗⃗?
Calculate the resultant using the Pythagorean theorem.
p.11
Unit Vectors and Their Applications
What are the Cartesian coordinate axis unit vectors?
Unit vectors for each positive coordinate axis direction in a Cartesian system.
p.4
Unit Conversion and Dimensional Analysis
How can you convert 0.02 inches to meters?
0.02 in = 0.02 x 0.0254 m = 0.000508 m = 5.08 x 10^-4 m = 0.503 mm or 508 μm.
p.10
Scalars and Vectors: Definitions and Differences
What are the components of vector A?
Ax (x component) and Ay (y component).
p.6
Uncertainty in Measurement and Error Analysis
What is a common rule of thumb for determining uncertainty?
Take one-half the unit of the last decimal place in a measurement.
p.12
Vector Representation and Addition Methods
What is the sum of vectors expressed in unit vector notation?
It is the sum of the x components times î, plus the sum of the y components times ĵ, plus the sum of the z components times k̂.
p.13
Measurement and Units in Physics
What is measurement?
The act of comparing a physical quantity with its unit.
p.13
Uncertainty in Measurement and Error Analysis
What does uncertainty in measurement indicate?
The range of possible values of the measure, covering the true value and characterizing the spread of measurement results.
p.11
Unit Vectors and Their Applications
How is a unit vector typically denoted?
With a 'hat' symbol (e.g., ̂).
p.11
Unit Vectors and Their Applications
What additional unit vector is present in a three-dimensional coordinate system?
The unit vector ̂ in the +z direction.
p.11
Vector Representation and Addition Methods
What is the advantage of using unit vector notation for vector addition?
It allows for easy factoring of individual unit vectors from multiple terms.
p.6
Significant Figures and Their Rules
How many significant digits does the measurement 0.428 m have?
It has three significant digits.
p.8
Scalars and Vectors: Definitions and Differences
What is a vector?
A quantity specified by both a magnitude and direction in space.
p.8
Vector Representation and Addition Methods
What does the length of a vector represent?
The magnitude of the vector.
p.7
Significant Figures and Their Rules
What is Rule 2 for significant digits when adding or subtracting?
The number of significant digits should equal the smallest number of decimal places of any term in the sum or difference.
p.14
Unit Vectors and Their Applications
What is the significance of finding a unit vector?
It indicates direction without magnitude.
p.9
Vector Representation and Addition Methods
What is the parallelogram law of vector addition?
The resultant of two vectors is the diagonal of the parallelogram formed by those vectors as adjacent sides.
p.4
Unit Conversion and Dimensional Analysis
How many cubic meters are in 250,000 cubic centimeters?
To convert, use the appropriate conversion factor.
p.4
Uncertainty in Measurement and Error Analysis
What is uncertainty analysis?
The art of estimating deviations from the true value of a measured quantity.
p.6
Uncertainty in Measurement and Error Analysis
What does a measurement of 5.7 cm imply about its uncertainty?
It implies an uncertainty of 0.05 cm, meaning 5.65 cm ≤ L ≤ 5.75 cm.
p.8
Scalars and Vectors: Definitions and Differences
What is a scalar?
A quantity specified by a number and unit, having magnitude but no direction.
p.6
Significant Figures and Their Rules
When is a zero counted as a significant figure?
If it has a non-zero digit anywhere to its left, then it is significant.
p.8
Vector Representation and Addition Methods
What is a zero vector?
A vector of zero length, represented as a point.
p.13
Basic and Derived Physical Quantities
What are basic quantities?
Quantities that cannot be expressed in terms of any other physical quantity, such as length, mass, and time.
p.7
Significant Figures and Their Rules
What are the general rules for determining significant digits in a number?
1. All non-zero numbers are significant. 2. Zeros within a number are always significant. 3. Zeros that set the decimal point are not significant. 4. Zeros not needed to hold the decimal point are significant. 5. Zeros that follow a number may be significant.
p.13
Vector Representation and Addition Methods
What is a resultant vector?
A single vector obtained by adding two or more vectors.
p.9
Vector Representation and Addition Methods
What trigonometric functions are used to find the components of a vector?
Sine and cosine functions.
p.11
Unit Vectors and Their Applications
What does A_x ̂ represent in vector A?
The x-component of vector A with magnitude |A_x| in the +x direction.
p.6
Uncertainty in Measurement and Error Analysis
What is the uncertainty in a digital measuring device?
It is equal to the smallest increment.
p.6
Uncertainty in Measurement and Error Analysis
What is the preferred form for stating a measurement?
Measurement = x best ± uncertainty.
p.6
Significant Figures and Their Rules
What is the accepted convention for reporting uncertain digits?
Only one uncertain digit should be reported.
p.6
Significant Figures and Their Rules
How many significant figures does the number 0.0005 have?
It has only one significant figure.
p.8
Scalars and Vectors: Definitions and Differences
What happens when you multiply a vector by a negative number?
The direction of the vector is reversed.
p.8
Scalars and Vectors: Definitions and Differences
What is the relationship between velocity and displacement?
Displacement is obtained when velocity (a vector) is multiplied by time (a scalar).
p.14
Unit Vectors and Their Applications
What is the formula to find a unit vector in the direction of a resultant vector?
Divide the vector by its magnitude.
p.9
Vector Representation and Addition Methods
What does the resultant vector represent in graphical vector addition?
The vector drawn from the tail of the first vector to the head of the last vector.
p.6
Uncertainty in Measurement and Error Analysis
How should uncertainty be stated when making a measurement?
It should be stated explicitly to avoid confusion.
p.10
Vector Representation and Addition Methods
How can the components Ax and Ay be combined?
They can be added to give back A as their resultant: A = Ax + Ay.
p.12
Unit Vectors and Their Applications
What does each component of a unit vector represent?
Each component is the corresponding component of the original vector divided by the magnitude of the original vector.
p.7
Significant Figures and Their Rules
What is the rule for zeros used only to locate the decimal point?
They are NOT significant.
p.7
Significant Figures and Their Rules
How many significant figures does the result of 9.65 cm + 8.4 cm - 2.89 cm equal?
15.2 cm, rounded to the nearest tenth.
p.13
Scalars and Vectors: Definitions and Differences
What is a vector?
A quantity specified by both a magnitude and direction in space.
p.13
Unit Vectors and Their Applications
What is a unit vector?
A vector that has a magnitude of one, is dimensionless, and specifies a direction.
p.13
Vector Representation and Addition Methods
What are the methods for adding vectors?
Graphical method of vector addition and Parallelogram law of vector addition.
p.11
Unit Vectors and Their Applications
What unit vectors exist in a two-dimensional x-y coordinate system?
The unit vector ̂ in the +x direction and the unit vector ̂ in the +y direction.
p.11
Unit Vectors and Their Applications
How can any vector be expressed in terms of unit vectors?
By using its components along the unit vectors, such as A = A_x ̂ + A_y ̂ + A_z ̂.
