🧪 Review 5&6 🧪 Flashcards
(23 cards)
Newton’s 1st law?
An object will not change its motion unless acted upon by an outside force. (inertia law)
Newton’s 2nd law?
Acceleration of an object depends on the force on the object and the mass of the object.
Newton’s 3rd law?
For every action force there is an equal and opposite reaction force.
What is inertia and what does it depend on?
Inertia is an object’s resistance to change motion. It depends on mass.
What is a force pair?
A force pair is the push that occurs between two objects. When one object pushes on another object, that object pushes back with an equal force in the opposite direction.
How can weight be calculated using the second law?
weight = mass x acceleration
What is momentum? What does it depend on?
Momentum is an object’s resistance to stopping. It depends on the mass of the object and its velocity.
Explain the Law of Conservation of Momentum.
The total momentum before a collision is equal to the total momentum after a collision. Momentum is never lost, only transferred between objects.
What is a machine? What does the defition mean?
A machine makes work easier.
Making work easier means a machine can change the size or direction of the input force.
Explain the force/distance trade-off.
The force/distance trade-off states that a machine can have a larger output force or a larger output distance but never both.
Describe the six simple machines.
A inclined plane is a ramp used to raise the load to a higher point.
A single fixed pulley is a roped in a grooved wheel. It changes the direction of the input force.
Movable pulleys and block and tackle systems are pulleys working together & have more output force than input force.
A screw is an inclined plane wrapped in a spiral.
A wedge is a double inclined plane that moves.
A wheel and axle has two parts, when you turn one the other also turns.
A lever pivots around a point called the fulcrum.
What is energy? Work? What units are used to measure energy?
Energy is the ability to do work. Work is done when a force moves an object in the direction of the force. Energy is measured in Joules.
What is kinetic energy? What does it depend on?
Kinetic energy is the energy of motion. It depends on the mass and velocity of an object.
What is gravitational potential energy?
Potential energy is energy caused by the position of an object. Also considered “stored” energy.
What is elastic potential energy.
Potential energy is energy caused by changing the shape of an object. Also considered “stored” energy.
What is thermal energy and what does it depend on?
Thermal energy is the total kinetic energy of the MOLECULES of a substance. It depends on the temperature of the substance and the mass of the substance.
How is thermal energy different from temperature?
Thermal energy is the TOTAL kinetic energy while temperature is the AVERAGE kinetic energy of the molecules.
What is a wave? Medium?
A wave is a disturbance that transfers energy. The matter through which a wave travels is called a medium.
Crest def?
Highest point of a transverse wave.
Trough def?
The low points on a transverse wave.
Wavelength def?
Crest to crest or trough to trough.
Amplitude def?
The height of a wave.
Frequency def?
The number of oscillations (waves) produced in a certain amount of time.
