Units and Measurements
33 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Match the following prefixes with their corresponding magnitudes:

kilo = $10^3$ micro = $10^{-6}$ giga = $10^9$ milli = $10^{-3}$

Match the base quantity with its corresponding SI unit:

Mass = kg Time = s Electric Current = A Temperature = $^oK$

Match the derived quantity with its corresponding SI unit:

Volume = $m^3$ Speed = m/s Force = N Work = J

Match the prefix symbol with its prefix name:

<p>T = Tera n = Nano $$\mu = Micro p = Pico</p> Signup and view all the answers

Match the following derived units with their equivalent expressions in base SI units:

<p>Newton (N) = kg⋅m/s² Joule (J) = kg⋅m²/s² Watt (W) = kg⋅m²/s³ Pascal (Pa) = kg/(m⋅s²)</p> Signup and view all the answers

Match each type of electromagnetic radiation with its approximate wavelength:

<p>Gamma Ray = $10^{-12}$ m UV Ray = $10^{-8}$ m Infra-red = $10^{-5}$ m Radiowave = $10^{3}$ m</p> Signup and view all the answers

Match the quantity with its corresponding commonly used symbol:

<p>Potential difference/voltage = V Current = I Resistance = R Half-life = $t \frac{1}{2}$</p> Signup and view all the answers

Match each quantity with its SI unit:

<p>Energy = J Frequency = Hz Pressure = Pa Power = W</p> Signup and view all the answers

Match the following quantities to whether they are scalar or vector:

<p>Speed = Scalar Velocity = Vector Force = Vector Mass = Scalar</p> Signup and view all the answers

Match the instrument to what it measures:

<p>Metre Rule = Length up to one metre Measuring Tape = Lengths up to several meters Digital Calipers = Precise length, thickness, and diameter Digital Micrometer Screw Gauge = Very small lengths, high precision</p> Signup and view all the answers

Match these quantities to their correct units:

<p>Wavelength = m Acceleration = m/s² Force = N Density = g/cm³</p> Signup and view all the answers

Match these angles to their symbols:

<p>Angle of incidence = i Angle of reflection = r Angle of refraction = r Focal Length = f</p> Signup and view all the answers

Match These Quantities with their Formula Symbols

<p>Time = t Period = T proton number = Z nucleon number = A</p> Signup and view all the answers

Match these examples with there type of quantity

<p>Distance = Scalar Work done = Scalar Displacement = Vector Moment of force = Vector</p> Signup and view all the answers

Match these formulas with their corresponding units

<p>Area = $m^2$ Volume = $m^3$ Speed = m/s Activity of a radioactive source = A</p> Signup and view all the answers

Why is it recommended to avoid using the zero mark on a metre rule for taking measurements?

<p>The zero mark might be worn out due to wear and tear, leading to inaccurate readings.</p> Signup and view all the answers

Explain how taking multiple measurements and calculating the average helps in minimizing random errors.

<p>Random errors cluster around the true value. Averaging the measurements cancels out the positive and negative deviations leading to a result closer to the true value.</p> Signup and view all the answers

What is the significance of calibrating equipment in the context of measurement, and what type of error does it primarily address?

<p>Calibration ensures the equipment provides accurate readings by correcting systematic errors to align with known standards.</p> Signup and view all the answers

Describe a situation where using digital calipers would be more appropriate than using a standard ruler. Explain your reasoning.

<p>When measuring the diameter of a pipe. Digital calipers provide more accurate measurements than a standard ruler due to their design and digital display.</p> Signup and view all the answers

What is the function of the locking screw on digital calipers, and why is it important in certain measurement scenarios?

<p>The locking screw secures the jaws of the calipers at a specific position. It is important when you need to transfer a measurement or ensure the calipers do not move before reading the measurement.</p> Signup and view all the answers

Explain the purpose of the ratchet on a micrometer screw gauge and why it is important for accurate measurements?

<p>The ratchet applies consistent pressure between the spindle and anvil. It prevents over-tightening, which could deform the object or the micrometer, ensuring accurate measurements.</p> Signup and view all the answers

A student consistently measures the length of a metal rod to be 25.1 cm using a particular ruler, even though the actual length is 25.3 cm. What type of error is most likely occurring, and how could the student address it?

<p>This is likely a systematic error. The student should calibrate the ruler against a known standard or use a different, calibrated measuring tool.</p> Signup and view all the answers

A scientist is using a digital caliper to measure the internal diameter of a pipe. Describe the steps they should take to ensure an accurate measurement, considering potential sources of error.

<p>First, calibrate the calipers. Next, use the internal jaws to measure the diameter. Then, ensure the jaws are properly aligned inside the pipe. Finally, lock the screw and record the measurement.</p> Signup and view all the answers

The ______ of an instrument refers to the smallest unit it can measure.

<p>precision</p> Signup and view all the answers

When using digital calipers, measurements are typically recorded to ______ mm to account for significant sources of error.

<p>0.1</p> Signup and view all the answers

To measure the thickness of a sheet of paper, one could use a ______, because it can measure to $0.001cm$.

<p>micrometer screw gauge</p> Signup and view all the answers

The SI unit for measuring ______ is the second, denoted as (s).

<p>time</p> Signup and view all the answers

A complete ______ of a simple pendulum occurs when it swings from its starting point, moves to the opposite side, and returns to the original starting point.

<p>oscillation</p> Signup and view all the answers

The period of a simple pendulum, or the time taken for one complete oscillation, depends on gravitational field strength and the ______ of the pendulum.

<p>length</p> Signup and view all the answers

The period of oscillation for a simple pendulum is independent of the ______ of the pendulum bob.

<p>mass</p> Signup and view all the answers

The period of a complete oscillation depends on the gravitational field strength and ______ of the pendulum.

<p>length</p> Signup and view all the answers

Since human reaction time, ranging from 0.3 s to 0.5 s, introduces a random error, stopwatch readings are typically recorded to one ______ to account for this variability.

<p>decimal place</p> Signup and view all the answers

All physical quantities consist of a numerical ______ and a unit, allowing for standardized measurement and comparison.

<p>magnitude</p> Signup and view all the answers

Flashcards

Physical Quantity

A measurable aspect of the physical world, consisting of a numerical value and a unit.

Kilogram (kg)

The standard unit of mass in the SI system.

Meter (m)

The standard unit of length in the SI system.

Derived Quantity

A combination of base units to express more complex measurements.

Signup and view all the flashcards

Micro ($\\mu$)

A prefix that represents $10^{-6}$ or one millionth.

Signup and view all the flashcards

Scalar Quantity

Physical quantities with magnitude only.

Signup and view all the flashcards

Vector Quantity

Physical quantities with both magnitude and direction.

Signup and view all the flashcards

Distance

The distance covered by an object.

Signup and view all the flashcards

Velocity

The rate at which an object changes its position.

Signup and view all the flashcards

Force

A push or pull that can cause a change in motion

Signup and view all the flashcards

Acceleration

The rate of change of velocity.

Signup and view all the flashcards

Meter Rule

Instrument to measure up to one meter lengths

Signup and view all the flashcards

Measuring Tape

Instrument to measure lengths up to several meters, straight or curved.

Signup and view all the flashcards

Displacement

The shortest distance from start to finish with direction.

Signup and view all the flashcards

Parallax Error: How to Avoid

Positioning your eye directly above the measurement to avoid skewed readings.

Signup and view all the flashcards

Random Errors

Errors that are unpredictable and vary around a mean value; reduce by averaging multiple readings.

Signup and view all the flashcards

Systematic Errors

Errors that are constant and predictable; correct by calibrating equipment.

Signup and view all the flashcards

Digital Calipers: Use

To measure internal and external diameters plus depth of objects accurately.

Signup and view all the flashcards

Outside Jaws (Callipers)

Used to measure the external diameter or width of an object.

Signup and view all the flashcards

Inside Jaws (Callipers)

Used to measure the internal diameter of an object

Signup and view all the flashcards

Ratchet (Micrometer)

Used to adjust the spindle of a micrometer so it gently contacts an object.

Signup and view all the flashcards

Micrometer Screw Gauge

Used for measuring very small objects digital callipers cannot measure.

Signup and view all the flashcards

Instrument Precision

Smallest unit an instrument can measure.

Signup and view all the flashcards

Measuring time instruments

Tool used to measure time, accuracy depends on the instrument.

Signup and view all the flashcards

Complete Oscillation

Motion of a pendulum from the starting point, through its arc, and back to the starting point.

Signup and view all the flashcards

Period of a Simple Pendulum

Time for one complete back-and-forth swing of a pendulum.

Signup and view all the flashcards

Period Dependence (Pendulum)

The period is affected by gravity and pendulum length.

Signup and view all the flashcards

Period Independence (Pendulum)

The period does not change if the mass changes

Signup and view all the flashcards

Human Reaction Time

Typical delay between stimulus and response.

Signup and view all the flashcards

Accounting for Reaction Time

Account for reaction time errors when measuring time.

Signup and view all the flashcards

Study Notes

Simple Pendulum

  • The period of a simple pendulum is the time taken for one complete oscillation.
  • The period of oscillation depends on gravitational field strength and length of the pendulum.
  • The period of a simple pendulum is independent of the mass of the pendulum bob.

Human Reaction Time

  • Most stopwatches measure time to a precision of 0.01 s.
  • Human reaction time is about 0.3 s – 0.5 s, creating a degree of random error.
  • Human reaction time readings are usually recorded to 1 d.p. to account for this error.

Avoiding Errors in Measurement

  • When using a metre rule, eyes should be positioned perpendicularly to the rule to avoid parallax errors.
  • Avoid using the zero mark of the metre rule as a start point for measurements.
  • Wear and tear may make it unsuitable for measuring purposes and introduce errors to the readings if the zero mark is used.

Digital Calipers

  • They measure internal and external diameters of an object accurately.
  • The tail of the calipers measure depth of an object.

Digital Micrometer Screw Gauge

  • Used for measuring objects too small for digital calipers.

Base Quantities and SI Units

  • All physical quantities consist of a numerical magnitude and a unit.
  • Base Quantity Mass’ SI unit is kg.
  • Base Quantity Length’s SI unit is m.
  • Base Quantity Time’s SI unit is s.
  • Base Quantity Current’s SI unit is A.
  • Base Quantity Temperature’s SI unit is K.

Derived Quantities and SI Units

  • Derived Quantity Volume’s SI unit is m^3.
  • Derived Quantity Speed’s SI unit is m/s.
  • Derived Quantity Acceleration’s SI unit is m/s^2.
  • Derived Quantity Force’s SI unit is N or kgm/s^2.
  • Derived Quantity Work’s SI unit is J or kgm^2/s^2.

Prefixes

  • The prefix "tera" has the symbol T and magnitude 10^12.
  • The prefix "giga" has the symbol G and magnitude 10^9.
  • The prefix "mega" has the symbol M and magnitude 10^6.
  • The prefix "kilo" has the symbol k and magnitude 10^3.
  • The prefix "milli" has the symbol m and magnitude 10^-3.
  • The prefix "micro" has the symbol μ and magnitude 10^-6
  • The prefix "nano" has the symbol n and magnitude 10^-9.
  • The prefix "pico" has the symbol p and magnitude of 10^-12.
  • The prefix “deci” has the symbol d and magnitude 10^-1
  • The prefix "centi" has the symbol c and magnitude 10^-2. </existing_notes>

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

IMG_0232.jpeg
IMG_0233.jpeg
IMG_0234.jpeg
IMG_0235.jpeg
IMG_0236.jpeg

Description

Overview of physical quantities, base and derived SI units. Includes common prefixes such as kilo, mega, and giga. All physical quantities consist of a numerical magnitude and a unit.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser