Physics Concepts Quiz

Radioactive Counting Error

• If radioactive counting is measured for four times longer, while maintaining constant activity, the absolute error doubles.

SI Units

• Speed and weight are not SI units.

Stochastic Biological Effects

• The frequency of stochastic effects increases with the dose.
• These effects are heritable.

Light Ray Path in the Eye

• The direction of light rays changes most significantly as they enter the cornea.

Volume Velocity of Viscous Liquid

• Volume velocity is directly proportional to the pressure difference.

Sound Source and Detector

• If a sound source approaches a detector, the detected frequency will be higher than the emitted frequency.
• Stokes' law implies that the diffusion constant is inversely proportional to the medium's viscosity.

Blood Dilution Isotopes

• ⁵¹Cr and ¹³¹I are used to measure blood dilution volume.

True Statements (Question 8)

• Transmission speed of higher frequency sounds is lower than the speed of lower frequency sounds.
• Mediated diffusion is faster than simple diffusion.

Radioactive Isotope Decay Constant

• The decay constant of an isotope with a 1-second half-life is approximately 0.7/s.

Resting Brain EEG Waves

• The resting brain emits alpha waves.

Biconcave Lens

• A biconcave lens is a diverging lens.
• The refractive index of the lens being greater than the refractive index of the medium is a property.

Imaging Equipment and Resolution

• The resolution of brain images in CT scans is impacted by skull absorption.

Laplace Law

• In pipes with circular cross-sections, the tension is created by pressure.

Blood Pressure Change (Sudden Standing Up)

• Blood pressure in the brain decreases when a person abruptly stands up.

Laminar Blood Velocity Change

• If the radius of a blood vessel increases by 19%, the volume velocity of laminar blood doubles (approximately).

Imaging Procedure Using Ionizing Radiation

• CT and PET scans use ionizing radiation to produce images.

Dark-Adapted vs. Light-Adapted Eye Sensitivity

• The dark-adapted eye is more sensitive than the light-adapted eye.

Coherent Light Wave Interference

• Two light waves cause permanent interference only when they are coherent and their phase difference is constant.

SI Unit for 1/s

• The SI unit for 1/s is frequency and decay constant.

Korotkoff Noise

• Korotkoff noise occurs when the air pressure in a blood pressure cuff is lower than the pressure created by the heartbeat.

Ionizing Radiation Biological Effect

• 3 MeV energy alpha radiation has a greater biological effect than other ionizing radiation at the same transmitted energy.

Ultracentrifugation

• Lower frictional coefficient leads to faster, and smaller diffusion constants lead to slower movement in ultracentrifugation.

Positron Beta Decay

• In positron beta decay, the atomic number increases by one, while the mass number remains unchanged.

Effective Half-Life of Radioactive Isotope

• The effective half-life of a radioactive isotope introduced in the body is always less than its biological half-life and it equals the reciprocal of the sum of reciprocals of the individual half-lives.

Alpha Particle Properties

• Alpha particles are not protons, nor are they high-energy photons; instead, they are doubly ionized helium atoms.

EEG Wave Amplitude (50-100 μV)

• Delta waves have amplitudes from 50 to 100 μV.

Isotope Decay Percentage

• After 20 minutes, 75% of a 10-minute half-life isotope 13N has decayed.
• After 40 minutes 93.75 % of a 10-minute half-life 14N isotope has decayed.

Refractive Index of a Lens System

• The refractive index of a lens system consisting of two thin lenses in contact is the sum of the refractive indices of the lenses.

Radioactive Source Activity

• The activity of a radioactive source is the number of radioactive decays per second.

Stokes' Law

• Stokes' law describes the resistance force acting on a spherical body moving in a viscous liquid.

Imaging Procedure Without EM Radiation

• Echoencephalography does not use electromagnetic radiation.

Refraction at a Boundary

• The degree of refraction depends on the refractive indexes of the two media and their densities.

Light Wave Interactions

• Light waves added up when two light waves meet.

Torque Types

• Bending and Twisting

Thermodynamically Isolated System (example)

• This is a system that cannot exchange energy or matter with its surroundings.

When the Internal Temperature is Constant

• An isothermal thermodynamic process occurs when the internal temperature is constant.

Electron Ionization

• Ionization occurs when electrons are freely dispersed from their parent atom.

Kinetic Energy of a Bird

• If a bird weighs 1kg and flies at 36 km/ hr, the kinetic energy is 50 Joules.

Frequency of Sound

• The dimensions corresponding to sound are ground frequencies.

X-ray Attenuation Mechanisms (example)

• Photoelectric absorption, pair production, and Compton scattering are mechanisms for x-ray attenuation

Abbe Theory Application (example)

• The Abbe theory is valid for light refraction.

Extensive vs. Intensive Dimensions

• Extensive dimensions, like mass and volume, are additive.

Ionising Radiations

• Ionized radiations are Beta and Gamma radiation.

Lens Errors

• Lens errors include chromatic and spherical aberrations.

Beta Radiation Range

• Beta radiation ranges from a few centimeters to several meters in air and a few millimeters in soft tissues.

Boltzmann Distribution

• Boltzmann distribution does not explicitly describe effective half-lives or bound electrons.

Heat Transport Processes

• Conduction, convection, and radiation are heat transport processes.

Bremsstrahlung

• The power of Bremsstrahlung radiation depends on the accelerating voltage.

Dimension of Impulse (example)

• The dimension of impulse is kg⋅m/s.

Atomic Nucleus Size (example)

• The light atomic nucleus is approximately 10-15 meters in size.

Beta Radiation Properties

• Beta radiation has a continuous spectrum.
• Maximum energy for a given radioactive nuclide determines the upper limit of the emission.

Mesophases properties (example)

• Mesophases exhibit properties like anisotropy. This means different properties in different directions.

Half-life Remainder (example)

• After three half-lives, 12.5% of a substance will remain.

Lambert-Beer's Law

• Lambert-Beer's Law explains light reflection in thin solutions.

Voltage-Clamp Technique

• The voltage-clamp technique keeps the membrane voltage at a set artificial value. (example)

EEG Wave Amplitude (example)

• Beta-EEG waves usually have an amplitude less than 20 μV.

Absolute Error (example)

• The absolute error of the difference between two measurements is the square root of the sum of the squares of the two individual absolute errors.

Decay Constant of a Radioactive Element

• The radioactive decay constant is inversely proportional to the half-life.

Microwave Diathermy Frequency

• The frequency used in microwave diathermy is 2540 MHz.

Plasmolysis-inducing Solution (example)

• Hypertonic solutions cause plasmolysis.

Beta Particle Properties

• Beta particles are high energy electrons, not hydrogen nuclei.

Radiation Dose Units

• The SI unit for radiation dose is C/kg.

Condenser Space Diathermy Frequency (example)

• The frequency used in condenser space diathermy is 0.03 GHz.

Object and Lens Focal Length

• A real object positioned within the focal length of a converging lens produces a virtual and upright image.

Diffusion Constant Dependence

• Diffusion constant does not depend on the medium's density or pH.

Alpha Particle Composition

• Alpha particles are doubly ionized helium atoms (He nuclei).

Sound Penetration and Diffusion

• The penetrating ability of higher-frequency sounds is lower than lower-frequency sounds.
• Mediated diffusion is faster than simple diffusion (example).

Refraction and Medium Density

• The degree of refraction at the boundary of two media depends on the density of the two media.

Electron Wavelength

• The wavelength of an electron in a vacuum depends on various factors. (example)

Visual Acuity of the Eye

• The light-adapted eye is the most sensitive and has higher visual acuity. It does not have poor visual acuity.