Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
44 Cards in this Set
- Front
- Back
|
Force is measured in? |
Newtons |
|
|
F=velocity x acceleration |
1. Strength 2. Direction |
|
|
Symbolism of Force is what? |
arrows -direction=direction -length=strength |
|
|
Net Force |
combined force on an object |
|
|
Unbalanced forces cause what? |
Causes objects to start moving, stop moving, and change direction |
|
|
Balanced force |
is equal and stops motion |
|
|
Friction |
created by two objects by rubbing together -more force=more friction -stronger is surface is rougher -even smooth surfaces have microscopic friction Most friction-opposite the movement |
|
|
Conservation of energy |
energy is neither created nor destroyed - |
|
|
Think of the spinning top visualization |
-mechanical energy
-air heat-moves up -Total amount remains the same -If you add the heat and put together, you can calculate the total energy in the system |
|
|
Motion |
an object in motion if its location changes relative to a second point -the reference point or the thing used to determine if something is in motion |
|
|
Speed |
measure of movement; can be calculated by diving the distance traveled by the time moving Distance/Time |
|
|
Velocity |
speed+direction -transportation -rotation -vibration |
|
|
Gravity |
a force that pulls objects toward each other -all objects attract each other, but we don't notice that because the force is too small |
|
|
two factors that influence gravity? |
Mass and Distance |
|
|
________ measures the gravitational force of the Earth |
Weight |
|
|
___________ stays constant; ___________ changes. |
Mass, weight |
|
|
Why do you way less on the moon? |
Because the moon has less mass |
|
|
Free Fall |
no force but gravity, actin on the object |
|
|
As an object falls, it's speed ______________. |
Increases |
|
|
Falls at ___________ m/s2 |
9.8 |
|
|
In a vacuum, objects go at what rate? |
exactly the same rate |
|
|
Air resistance |
Object in air experience fluid More surface area=more air resistance |
|
|
Newton's First law or Law of Inertia |
an object at rest will stay at rest -an object in motion will stay in motion unless acted upon by an outside force |
|
|
On earth, gravity and friction are often ____________ forces, objects flying through the air are stopped by __________ and friction |
unbalanced, gravity |
|
|
Forces of Inertia |
the tendency of an object to resist motion |
|
|
Newton's 2nd Law |
-Increasing speed increases force -increasing mass increases force -reducing speed creases force: decreasing speed rapidly puts strain on the object |
|
|
In an object stops suddenly, the force is ______________ than it was before it slows. |
greater. (Newton's 2nd law) |
|
|
Newton's 3rd Law |
for every action there is an equal and opposite reaction -the concrete string, the egg with as much force as the egg strikes the concrete -This means that for every action there is an opposite reaction |
|
|
Active force |
-caused force
|
|
|
Reactive force |
the resulting force |
|
|
Jumping active and reactive? |
active is upward motion, reactive if falling down |
|
|
Running active and reactive? |
active is forward, reactive is backward |
|
|
Momentum |
moving things have a quality of speed-affected by mass and velocity |
|
|
Colliding objects ____________ their momentum unless outside forces act on them. |
conserve |
|
|
momentum can be _________ but not lost |
transferred |
|
|
balancing momentum and gravity |
satellites are falling projectiles that balance the two forces the balance creates a centripetal force |
|
|
Newtonian Demonstrator |
1 ball released moves the balloon the opposite side at the same rate 2) Two balls raised moved 2 on opposite end at the same rate 3) 3 balls raised moved the energy to 3 balls opposite |
|
|
Non-renewable energy sources |
most energy comes from natural resources-found, not made |
|
|
All natural resources can be __________. |
Reused |
|
|
Non renewable resources are? |
Limited |
|
|
Are fossil fuels renewable or Non renewable? |
NR |
|
|
Fossil Fuels |
Organic pressed under surface Coal, oil, natural gas 94% of US energy comes from renewable resources |
|
|
Pollutants |
sulfur exists in most fossil fuels. _Binds with water vapor -sulfuric acid collects in clouds -acid rain |
|
|
Oil spills |
caused by oil machine malfunction, hurting ecosystem -fills stuff |
