Science Midterm Study Guide
Heat to heat transfer
Kinetic energy: energy of motion
Heat: thermal energy or total of all energy within a substance
Motion of molecules
Vibrates and moves in each state of matter
Solid: slowest
Liquid: faster than solid, slower than gas
Gas: fastest
Law of Conservation of Energy: states that energy can neither created nor destroyed, it simply changes form
Thermal energy in freezing and boiling materials
Freezing: decreases kinetic energy; molecules move slowly and closer together.
Boiling: increases kinetic energy; molecules move faster and farther apart.
Solutes: salt (how it affects boiling and freezing)
Boiling: increases boiling point
Boiling point: the temperature at which a liquid becomes a gas
Freezing: decreases freezing point
Freezing point: the temperature at which a liquid becomes a solid
Specific heat capacity: the amount of heat (joules) that is required to raise the temperature of 1 gram of a substance by 1 degree centigrade
Joules: unit of energy
Heat transfer: transfer of thermal energy from areas of high temperature to low temperature
Friction
Frictional force: The force that prevents two objects from easily moving against one another
Acceleration: the rate an object changes velocity
Positive acceleration: speed increases as it moves away from its starting position
Negative acceleration: speed decreases as it moves away from its starting position
Relationship between weight and friction
The more weight, the more frictional force.
Surface area in friction
Friction stays the same on an object, no matter the surface area
What affects friction
The smoothness/roughness of the surface.
Smoother the surface, less friction
Rougher the surface, more friction
Coefficient of friction: a number that describes the degree of mechanical and molecular interaction between forces
As friction increases, coefficient of friction increases
Applied force: force that is applied to an object from an outside force
FE = ma : the sum of all forces equal to mass x acceleration
Soundwaves
Pressure waves: the moving wave that is produced by a standing wave moves back and forth
Standing waves: a wave that forms in a vibrating object. This wave does NOT move through space, it forms due to the repeated vibrations of the object
Frequency vs pitch
Frequency: the back and forth vibrations which causes sound to occur rapidly or slowly
Pitch: how high or low the sound is
Low frequency= HIGH PITCH
High frequency= LOW PITCH
Speed of sound (in air and water)
Air: 346 m/s
Water: 1500 m/s
Greater attraction between particles = greater speed of sound
Formula of speed (s=wavelength x frequency)
Standing wave
2 nodes: beginning + end
2 antinodes: one up, one down
Science Midterm Study Guide
Heat to heat transfer
Kinetic energy: energy of motion
Heat: thermal energy or total of all energy within a substance
Motion of molecules
Vibrates and moves in each state of matter
Solid: slowest
Liquid: faster than solid, slower than gas
Gas: fastest
Law of Conservation of Energy: states that energy can neither created nor destroyed, it simply changes form
Thermal energy in freezing and boiling materials
Freezing: decreases kinetic energy; molecules move slowly and closer together.
Boiling: increases kinetic energy; molecules move faster and farther apart.
Solutes: salt (how it affects boiling and freezing)
Boiling: increases boiling point
Boiling point: the temperature at which a liquid becomes a gas
Freezing: decreases freezing point
Freezing point: the temperature at which a liquid becomes a solid
Specific heat capacity: the amount of heat (joules) that is required to raise the temperature of 1 gram of a substance by 1 degree centigrade
Joules: unit of energy
Heat transfer: transfer of thermal energy from areas of high temperature to low temperature
Friction
Frictional force: The force that prevents two objects from easily moving against one another
Acceleration: the rate an object changes velocity
Positive acceleration: speed increases as it moves away from its starting position
Negative acceleration: speed decreases as it moves away from its starting position
Relationship between weight and friction
The more weight, the more frictional force.
Surface area in friction
Friction stays the same on an object, no matter the surface area
What affects friction
The smoothness/roughness of the surface.
Smoother the surface, less friction
Rougher the surface, more friction
Coefficient of friction: a number that describes the degree of mechanical and molecular interaction between forces
As friction increases, coefficient of friction increases
Applied force: force that is applied to an object from an outside force
FE = ma : the sum of all forces equal to mass x acceleration
Soundwaves
Pressure waves: the moving wave that is produced by a standing wave moves back and forth
Standing waves: a wave that forms in a vibrating object. This wave does NOT move through space, it forms due to the repeated vibrations of the object
Frequency vs pitch
Frequency: the back and forth vibrations which causes sound to occur rapidly or slowly
Pitch: how high or low the sound is
Low frequency= HIGH PITCH
High frequency= LOW PITCH
Speed of sound (in air and water)
Air: 346 m/s
Water: 1500 m/s
Greater attraction between particles = greater speed of sound
Formula of speed (s=wavelength x frequency)
Standing wave
2 nodes: beginning + end
2 antinodes: one up, one down