export_basic physics

Question 1

Kinetic Energy

Answer 1

kinetic energy of an object is energy it possesses due to its motion

• “as the work needed to accelerate a body of a given mass from rest to a stated velocity”
• measured in joules
• can be imparted on object when an energy source is tapped to accelerate t
• also happen when an object w. kinetics slams into another object & kinetic energy from 1st is transferred to 2nd

Question 2

Kinetic Energy, con’t

Movement

Answer 2

Movement is an indication of the amount of kinetic energy an object has. Object will hold onto it’s kinetic energy until it is able to transfer it to something else, allowing it to slow down again.

Question 3

Newton’s first law of motion

Answer 3

things that are in motion stay in motion
or, more specifically,
“as long as an object has the same level of kinetic energy, it will move at a consistent velocity forward”

Question 4

Mechanical Energy

Answer 4

the ability of an object to do work.

• not a separate type of energy in the way that potential energy differ from each other.
• Mech energy is the potential energy available to an object added to all of the kinetic energy available to it, providing a total energy output. (p. 183)

Question 5

Potential Energy

Answer 5

2 main types of potential energy:

• gravitational potential energy &
• elastic potential energy.

“the potential an object has to act on other objects”
eg. in case of an object raised off groun & is waiting for gravity pulling at 9.8m/s*2 to grab hold of it & pull it towards the Earth.

Question 6

Energy:

Work & Power

Answer 6

Energy is the ability to do work.
Work in the physics sense is v. specific concept.
- is measured in joules (1 newton of force that displaces something by 1 meter)
J = Nm
When you add a unit of time to your calculations of work, you get: power.
the equation that measures power is
power = work/time e.g: Work measured in joules, time in seconds, power in watts….

Question 7

Force: Friction

Answer 7

Friction is the force that resists the motion of objects in relation to other objects:
2 main types of friction:
- static friction
- kinetic friction

Question 8

static friction

Answer 8

eg. when 1 stationary object is stacked on another stationary object like a book on a table. Static friction b/t the two determines how much sticking power there is between them - at what angle you’d have to tilt the table b4 the force of gravity overpowers the force of friction

Question 9

kinetic friction

Answer 9

is sort of the inverse of static friction.
- “it is the force that causes moving objects to slow down.”
Kinetic friction applies to 2 surfaces moving in respect to one another, such as the bottom of a snowboard & the snowy ground

Question 10

Fundamental Forces

Answer 10

• electromagnetism
• gravity
• strong & weak nuclear forces

Question 11

eletromagnetism

Answer 11

1 of 4 fundamental forces

• more common than gravity
• responsible for nearly all interactions in which gravity plays no part.
• holds negatively charged electrons in orbit around positively charged protons in the nucleus of an atom.
• also the force that joins atoms to each other to make molecules
• responsible for the fact that matter feels so solid.

Question 12

electromagnetism con’t

Answer 12

Electric current is nothing more than a steady flow of electrons, & by turning on the current you send electrons through the core.
- this aligns all the atoms in the metal so that they are parallel w. each other & this creates a magnetic field.