General Physics Lecture Notes Flashcards

A complete set of flashcards covering Sound, Light, SDGs, Electricity, Fluid Pressure, Dynamics, and Simple/Compound Machines based on the lecture notes.

What is sound, and what type of wave is it?

Sound is mechanical energy produced by vibrations. It is a longitudinal wave that requires a medium and cannot travel through a vacuum.

What is the difference between compression and rarefaction in a sound wave?

Compression is where particles are close together with high pressure, while rarefaction is where particles are spread apart with low pressure.

What is frequency in sound, and how does it relate to pitch?

Frequency is the number of waves per second, measured in Hertz ($\text{Hz}$). High frequency results in high pitch, and low frequency results in low pitch.

How does wave frequency relate to wavelength?

High frequency results in a short wavelength, while low frequency results in a long wavelength (as frequency increases, wavelength decreases).

What wave property determines loudness, and what is the unit of loudness?

Amplitude (wave height/strength) determines loudness, where high amplitude is loud and low amplitude is soft. Loudness is measured in decibels ($\text{dB}$). Amplitude affects loudness, not speed.

What is the speed of sound in normal air, and how does it vary across solids, liquids, and gases?

The speed of sound is about $343\,\text{m/s}$ in normal air. It travels fastest in solids, then liquids, and slowest in gases because particles in solids are more tightly packed.

What is timbre?

Timbre is the unique quality or color of sound that helps distinguish instruments or voices even when they have the same pitch and loudness.

What are the sound behaviors of reflection, refraction, and absorption?

Reflection produces an echo; refraction is bending through air layers with different temperatures; and absorption occurs when soft materials such as foam, curtains, and carpets absorb sound and reduce echoes.

Which Sustainable Development Goals (SDGs) correspond to energy, consumption, and climate?

SDG 7 is Affordable and Clean Energy, SDG 12 is Responsible Consumption and Production, and SDG 13 is Climate Action (7 = Energy, 12 = Consumption, 13 = Climate).

What is light, and what is its speed?

Light is an electromagnetic transverse wave that can travel through a vacuum at a speed of $3 \times 10^8\,\text{m/s}$.

How are crest, trough, wavelength, and frequency defined for light waves?

Crest is the highest point; trough is the lowest point; wavelength is the distance between corresponding points; and frequency is the number of waves per second, measured in Hertz ($\text{Hz}$).

How do Red and Violet light compare in wavelength and frequency within the visible light spectrum (ROYGBIV)?

Red light has the longest wavelength and lowest frequency, while Violet light has the shortest wavelength and highest frequency.

What are the definitions of reflection, refraction, dispersion, diffraction, interference, and polarization for light?

Reflection is bouncing; refraction is bending when light passes between media; dispersion is white light separating into colors; diffraction is spreading/bending around edges or openings; interference is overlapping waves (constructive = brighter, destructive = darker); and polarization is filtering light into one direction.

What are the descriptions of LED, LASER, fiber optics, Li-Fi, AR, and holograms?

LED is energy-efficient lighting; LASER is concentrated, coherent light; fiber optics transmits data using light; Li-Fi is wireless data using visible light; AR combines the real world with digital objects; and a hologram is a 3D-looking image using light.

What is electricity, and what is its basic path of flow?

Electricity is the flow of electrical charge/electrons. Its basic flow path is: Power Source $\rightarrow$ Conductor $\rightarrow$ Device.

How are power source, conductor, circuit, current, voltage, and power defined in basic electrical terms?

Power source provides electrical energy; conductor allows electricity to flow; circuit is a closed path for current; current is the flow of electric charge; voltage is electrical push/pressure; and power is the rate of energy transfer.

What five electrical hazards are identified in the notes?

Overloading (too many devices on one circuit), damaged insulation (exposed/damaged wires), damp conditions (water increases shock risk), faulty wiring (incorrect/loose/damaged wiring), and electrocution (harmful/deadly electric current through the body).

What are six key electrical safety practices listed in the notes?

Avoid overloading outlets; replace damaged cords; keep electrical equipment dry; never handle electrical devices with wet hands; have faulty wiring checked by a qualified professional; and never touch exposed wires.

What is the difference between energy conservation and energy efficiency?

Conservation means changing behavior/habits to use less electricity, whereas efficiency means using better technology to accomplish the same task with less energy.

What actions can reduce energy loss or wastage?

Use LED lights; turn off unused appliances; unplug devices when unnecessary; use energy-efficient appliances; maintain electrical systems; avoid overloading; promote renewable energy; and educate the community.

What is a fluid, and what is the formula and unit for pressure?

A fluid is a substance that can flow and take the shape of its container (includes liquids and gases). Pressure is force distributed over an area, calculated as $P = \frac{F}{A}$, with the unit Pascal ($\text{Pa}$) = $\text{N/m}^2$.

What factors determine fluid pressure, and what factors do NOT affect it?

Fluid pressure increases with depth, density, and gravity (remember D-D-G). It does not depend on container shape, width, or total volume.

What is Pascal's Principle, and which scientist is associated with it?

Formulated by scientist Blaise Pascal, Pascal's Principle states that pressure applied to an enclosed, incompressible fluid is transmitted equally and undiminished in all directions.

How do hydraulic systems function, and what are some of their applications?

Hydraulic systems use enclosed liquid to multiply force, allowing a small force on a small piston to produce a much larger lifting force on a larger piston. Applications include hydraulic brakes, lifts, excavators, bulldozers, bottle jacks, elevators, and automotive lifts.

What is buoyancy, and what does Archimedes' Principle state?

Buoyancy is the upward force exerted by a fluid on an immersed object that opposes weight, helps objects float, and makes submerged objects feel lighter. Archimedes' Principle states that the buoyant force equals the weight of the fluid displaced by an object.

What is the difference between rotate and revolve?

Rotate means to spin around its own axis, while revolve means to move around another object or external axis (e.g., Earth rotates on its axis and revolves around the Sun).

What are the definitions and formulas for momentum and impulse?

Momentum ($p = m v$) is moving power that depends on mass and velocity. Impulse is the change in momentum, where force absorption increases stopping time and reduces the force experienced.

What is a machine, and how are the six simple machines defined?

A machine is a device that makes work easier by changing the magnitude or direction of a force. Simple machines: Inclined plane (angled surface; reduces lifting effort), Lever (rigid bar rotating around a fulcrum), Screw (inclined plane wrapped around a shaft; rotational to translational), Pulley (grooved wheel and rope; fixed changes direction, movable reduces effort, compound greatly reduces effort), Wheel and axle (makes rotation easier), and Wedge (used for cutting/splitting).

What motion is associated with each of the simple machines?

Lever: rotational; Wheel and axle: rotational; Pulley: rotational + translational; Inclined plane: translational; Screw: rotational to translational; Wedge: translational.

What four forces act on machines?

Weight (gravitational pull), Tension (pulling force through a rope/string), Torque (turning effect of force), and Friction (opposes motion).

What is a compound machine, and what characterizes an efficient compound machine?

A compound machine consists of two or more simple machines working together (e.g., bicycle, car, crane, blender, can opener, nutcracker, stapler, pencil sharpener). Efficient compound machines have fewer moving parts, strong and maintained connections, combine advantages of simple machines, and save time and energy.