Unit 1: Physical Quantities and Measurement

Comprehensive practice flashcards in fill-in-the-blank style covering Unit 1: Physical Quantities and Measurement, including fundamental and derived quantities, measuring instruments, zero errors, density, volume, prefixes, and significant figures.

The word physics is derived from the Ancient Greek word 'physicos', meaning __________.

'knowledge of nature'

__________ physicists observe nature and solve mysteries by presenting theories with a mathematical approach, whereas experimental physicists test those theories with experiments.

Theoretical

Physics is defined as the branch of science which observes nature, represents it mathematically, and concludes with the __________.

experiment

The branch of physics mainly concerned with the laws of motion and gravitation is known as __________.

Mechanics

The branch of physics that deals with heat and temperature and their relation to energy and work is called __________.

Thermodynamics

__________ is the branch of physics that studies the properties of charges in rest and motion.

Electricity

The branch of physics that deals with the composition, structure, and properties of the atom is called __________.

Atomic physics

The branch of physics that studies physical aspects of light and its properties with the help of optical instruments is __________.

Optics

__________ physics deals with the constituents, structure, behavior, and interactions of atomic nuclei.

Nuclear

The study of celestial objects with the help of the laws of physics is known as __________.

Astrophysics

The study of the ionized state of matter and its properties is known as __________ physics.

Plasma

The study of the internal structure of the Earth is known as __________.

Geo physics

A physical property of a phenomenon, body, or substance that can be quantified by measurement is known as a __________.

physical quantity

Physical quantities that cannot be explained by other physical quantities are called __________ physical quantities.

fundamental

In the SI system, the unit for amount of substance is the mole, while luminous intensity is measured in __________.

candela

Elastic modulus, plane angle, and solid angle are examples of physical quantities that are __________.

unit-less

The notion of physical dimension of a physical quantity was introduced in 1822 by __________.

Joseph Fourier

In the SI system, the derived unit of force is the Newton ($\text{N}$), and the derived unit of acceleration is expressed as __________.

$$\text{m/s}^2$$

The smallest measurement that an instrument can perform is restricted by its __________.

least count

The meter ($\text{m}$) is defined as the length of the path traveled by light in vacuum during a time interval of __________ of a second.

$$1/299\,792\,458$$

In imperial-to-metric conversions given in the text, $1\,\text{inch}$ is equal to __________.

$$2.53\,\text{cm}$$

On a Vernier caliper, the main jaws measure external diameter, whereas the smaller jaws are used to measure the __________ diameter of objects.

internal

On a Vernier caliper, the main scale is fixed in place, while the sliding scale that opens and closes the jaws is called the __________ scale.

Vernier

When zero mark on the vernier scale is slightly to the right of the main scale zero, it indicates a __________ zero error, which must be subtracted from the reading.

positive

A micrometer screw gauge works on the principle of converting small distances into larger ones by measuring the __________ of the screw.

rotation

When taking a reading with a micrometer screw gauge, the thimble scale reading opposite the datum line is multiplied by the least count of __________.

$$0.01\,\text{mm}$$

When gripping an object in a micrometer screw gauge, the thimble is turned until the anvil and spindle gently touch the object, and then the __________ is turned until it starts to click.

ratchet

If the zero mark on the datum line cannot be seen when closing a micrometer screw gauge, a __________ zero error is present and must be added to the reading.

negative

The international prototype of the kilogram is a standard made of __________ kept at the International Bureau of Weights and Measures.

platinum-iridium

The standard mass cylinder for the kilogram is about $39\,\text{millimeters}$ wide by __________ millimeters tall.

$$39$$

The physical balance is a laboratory instrument used for measuring mass that operates on the principle of __________.

moments

In a physical balance, the __________ indicates whether the balance is horizontal.

plumb line

An electronic balance configured with integrated circuits determines mass based on the principle of __________.

balancing the forces

In 1967, the second was redefined as $9\,192\,631\,770$ times the period of vibration of radiation from the __________ atom.

cesium-133

A mechanical (analogue) stopwatch can measure a time interval up to __________ second.

$$0.1$$

A digital stopwatch can measure a time interval up to __________ second.

$$0.01$$

Operating a stopwatch manually causes a random error called human reaction time, which for most people is about __________.

$$0.3\text{--}0.5\,\text{s}$$

To eliminate random errors caused by human reaction time during time interval measurements, __________ can be used.

light gates

A unit __________ is a specifier that indicates multiples or fractions of units.

prefix

One hour equals $60\,\text{minutes}$, which is equivalent to __________ seconds.

$$3600$$

The SI prefix representing a multiplier of $10^{-15}$ is femto ($\text{f}$), while the prefix representing $10^{12}$ is __________.

tera

Numbers expressed in scientific notation consist of three parts: the coefficient, the base, and the __________.

exponent

In the states of matter, a __________ does not maintain a fixed shape, takes the shape of its container, and is not readily compressible.

liquid

In metric volume units, $1\,\text{m}^3$ is equal to __________ liters.

$$1000$$

To obtain an accurate volume reading using a measuring cylinder, the eye must be kept level with the bottom of the __________ of the liquid surface.

meniscus

The formula used to calculate the volume of a regular cylinder is __________.

$$\pi \times r^2 \times h$$

The volume of an irregular solid is calculated by subtracting the original volume of liquid from the __________ volume of liquid in a measuring cylinder.

raised

The density of a substance is defined as mass per unit volume and is denoted by the Greek letter __________.

$$\rho\text{ (rho)}$$

Relative density or specific gravity is a unitless ratio comparing the density of a substance to the density of water at __________.

$$4^\circ\text{C}$$

Humans floating without sinking while swimming in the Dead Sea in Jordan occurs because the high salt content greatly increases the __________ of the water.

density

In calculating the mass of an iron ball ($\rho = 7.8 \times 1000\,\text{kg/m}^3$) with a volume of $0.024\,\text{m}^3$, the resulting mass equals __________.

$$187.2\,\text{kg}$$

The number of reliably known digits in a value are known as __________.

significant figures

In determining significant figures, leading zeroes are __________, while trapped zeroes are always significant.

NOT significant

Trailing zeroes in a number are significant ONLY if an explicit __________ is present.

decimal point