Physical Science Flashcards
What is the formula for speed?
S= D/T (speed = distance divided by time)
What is the formula for velocity?
V= D/T (velocity = distance divided by time + direction)
What is acceleration?
A change in the velocity of an object
What is the formula for acceleration?
Delta V/Delta T (change in velocity over change in time)
What is Newton’s 1st Law?
The Law of Inertia: An object in motion tends to stay in motion, and an object at rest tends to stay at rest
What is required to overcome the inertia of an object?
an outside force
What is Newton’s 2nd Law?
The force/mass/acceleration relationship: the acceleration of an object is directly related to the force applied to an object and inversely related to the mass of the object
What is Newton’s 3rd Law?
For every action (or force), there is an equal and opposite reaction (or reactive force).
What is the difference between potential and kinetic energy?
potential energy is the possible energy of an object, kinetic energy is the energy of motion
What is work?
Force x Distance (measured in Joules)
What is power?
Work/Time (work divided by time, measured in watts or horsepower)
What is friction?
Friction is the force that the surfaces of two objects exert on each OR the force that an environment exerts on an object’s surface
What is gravity?
the universal attractive force between objects
What is static friction?
the friction present in objects that aren’t moving
Water and air moving against the surface of an object is an example of _________ friction.
fluid friction
Circular objects have rolling friction, which requires less force to overcome. Why is that the case?
reduced surface area contact between the objects
What are the simple machines?
levers, pulleys, screws, incline planes, wedges, wheel and axle
What is the purpose of simple machines?
to increase mechanical advantage, which means to get more output from the same amount of input
What is an example of a first class lever?
a seesaw (fulcrum in the middle between input and output forces)
What’s an example of a second class lever?
a wheelbarrow (output force between input and fulcrum)
What’s an example of third class lever?
Tweezers (input force between output and fulcrum)
What are the main forms of energy?
kinetic, radiant, thermal, chemical, electric, and potential
What can change an object’s potential energy?
a change in its circumstances (ex. how high the object)
What causes electricity?
the relationship between positive and negative charges caused by electrons
Finish this statement: __________ and ___________ are two sides of the same coin; they are connected forces.
Electricity and magnetism. You can use electricity to generate magnetism and magnetism to generate electricity
What is static electricity?
When a positive and negative quickly neutralize (balance) themselves, leaving both objects uncharged
What is current?
the steady flow of electrons through a conductor (powers every electronic device)
What form of electricity is lightning: static or dynamic (current)?
Static. Once lightning strikes, the charge is neutralized.
What is a conductor?
a material that allows for easy flow of electric current, like metal
What is an insulator?
a material that resists the flow of electric current, like rubber
What is the most common form of magnetism called?
Ferromagnetism (“ferrum” means iron in Latin, and most magnetic materials are iron-like.)
What two things control the magnetic interaction between two objects?
The strength of the charge and the distance between the objects
What is electromagnetism?
The term for the force of charges that control both electricity and magnetism.
