Physics Flashcards
What does work refer to in physics?
The force required to move an object a certain displacement
Work can be parallel to the displacement or at an angle.
What is the formula for calculating work?
W = F * d * cos(θ)
Where W is work, F is force, d is displacement, and θ is the angle from the horizontal.
What is the unit of work?
Joule (J)
Is work a scalar or vector quantity?
Scalar quantity
When is work considered positive?
When it causes displacement to an object
When is work considered negative?
When the object exerts work in the opposite direction
What is energy in the context of physics?
The capacity or capability of an object to do work
What unit is used for energy?
Joule (J)
What are the two types of energy?
- Kinetic energy
- Potential energy
What is potential energy (PE)?
The stored energy in an object
What determines potential energy?
An object’s position, properties, and the forces acting upon it
What is the formula for gravitational potential energy?
PE = m * g * h
Where m is the mass, g is gravity, and h is height.
What does kinetic energy (KE) refer to?
The energy used in motion
What is the formula for kinetic energy?
KE = 0.5 * m * v²
Where m is mass and v is velocity.
What does the Work-Energy Theorem state?
The total net work of a system is equal to the change of kinetic energy
What is mechanical energy (ME)?
The sum of the total potential energy and kinetic energy
What is the formula for mechanical energy?
ME = PE + KE
What is power in physics?
The rate at which work is done
What is the formula for power?
P = W/t
Where P is power, W is work, and t is time.
What is the unit for power?
Watt (W)
How many watts are in one horsepower?
746 W
What are fluids in physics?
States of matter that can flow, including liquids and gases
What does density (ρ) refer to?
The quantity in a given amount of space
What is the formula for density?
ρ = m/V
Where ρ is density, m is mass, and V is volume.
What is relative density or specific gravity?
The ratio of the density of a substance compared to the density of water
What does pressure refer to?
The force exerted perpendicular to a surface
What is the SI unit of pressure?
Pascal (Pa)
What are the three types of pressure?
- Static pressure
- Atmospheric pressure
- Gauge pressure
What is static pressure?
The pressure the fluid exerts at rest
What is atmospheric pressure?
The total force exerted by the weight of the air against a surface
What is gauge pressure?
The pressure relative to atmospheric pressure
What does Pascal’s Principle state?
When pressure increases at any point in a confined fluid, every other point will increase the same amount
What is buoyant force?
The net upward force a fluid exerts on an object
What does Archimedes’ Principle state?
An object submerged in a fluid experiences an upward buoyant force equal to the weight of the fluid displaced by the object
What is the principle of floatation?
For an object to float, the buoyant force must be greater than or equal to the object’s weight
What is fluid energy?
The energy carried by the fluid
What is steady flow?
The velocity of the fluid at any given point does not change with time
What is unsteady flow?
The velocity changes with time
What is laminar flow?
Smooth, parallel layers of fluid with minimal disruption between them
What is turbulent flow?
Chaotic, irregular fluctuations and mixing in the fluid
What is an ideal fluid?
An incompressible, inviscid fluid that follows a laminar flow
What does the continuity equation state?
The speed of fluid flow depends on the cross-sectional area
What does Bernoulli’s Principle state?
As the pressure of a fluid increases, the velocity decreases
What is Torricelli’s Law?
The speed of efflux of a fluid through a hole is given by v = √(2gh)
What does the Venturi Effect describe?
The reduction in fluid pressure when a fluid flows through a constricted section of a pipe
What is heat in physics?
The total kinetic and potential energy in an object
What is the SI unit of heat?
Joule (J)
What is temperature a measure of?
The average kinetic energy of all parts in an object
List the three types of heat transfer.
- Conduction
- Convection
- Radiation
What is conduction?
Heat transfer within solids due to molecular collision
What is convection?
Heat transfer within fluids through currents
What is radiation?
Heat transfer via electromagnetic waves
What does specific heat capacity refer to?
The energy required to change the temperature of a substance
What is latent heat?
The heat needed for a substance to undergo phase change without a change in temperature
What does thermal expansion refer to?
The change in measurement of an object when the temperature changes
What are the three classifications of systems in thermodynamics?
- Open
- Closed
- Isolated
What does the Zeroth Law of thermodynamics state?
If A is in thermal equilibrium with B, and B is in thermal equilibrium with C, then A is in thermal equilibrium with C
What is the First Law of thermodynamics?
Energy cannot be created or destroyed, only transformed
What does the Second Law of thermodynamics state?
Heat flows naturally from hot objects to cold objects, never the reverse
What is entropy?
A measure of a system’s disorder
What does the Third Law of thermodynamics state?
It is impossible to obtain absolute zero
What is a wave?
A traveling disturbance that carries energy from one place to another
What are the two main types of waves?
- Mechanical waves
- Electromagnetic waves
What is a mechanical wave?
A wave that requires a medium to travel
What is a transverse wave?
A wave that travels perpendicular to the direction of motion
What is a longitudinal wave?
A wave that travels parallel to the direction of movement
What are the parts of a transverse wave?
- Equilibrium position
- Crest
- Trough
- Amplitude
- Wavelength
What is reflection in wave behavior?
When waves bounce back after striking a barrier
What is refraction?
When waves bend due to a change in velocity as they pass obliquely from one medium to another
What is diffraction?
The property of a wave to travel around the edges of a barrier or through an opening
What is interference in wave behavior?
When two waves interact as they pass through the same medium
What is a standing wave?
A combination of two waves moving in opposite directions with the same amplitude and frequency
