🎉 Review 3&4 🎉 Flashcards
(19 cards)
Motion def?
Motion is the change in position of an object when compared to a reference point.
What is average speed and how is it calculated?
Average speed is the rate at which an object changes position over time.
Speed = distance
Time
Velocity definition?
The speed of an object and the direction of the motion.
Acceleration definition? Calculate? 2 km/hr/s meaning?
When velocity changes over time.
Acceleration = Delta V
———————T
A car accelerating at 2 km/hr/s is traveling 2 km/hr faster every second.
Speed definition?
The rate at which an object changes position.
Force definition?
A push or pull.
Balanced forces?
Forces are equal in magnitude and opposite in direction. There is no change in the motion of the object. Object is moving it will remain moving at a constant speed and direction.
Unbalanced forces definition?
Forces are unequal in magnitude. The object will change it’s motion , the speed and maybe the direction if motion will change.
Net force definition? Calculated?
Net force is the total of all of the forces acting on an object.
If the forces are in the same direction, add the forces. If the forces are in opposite directions, subtract the forces.
4 types of friction + definition.
Sliding-between 2 solid surfaces that rub against each other
Rolling-between a surface and a rolling object (usually less friction than sliding)
Fluid-friction between an object and a gas (air) or liquid (water)
Static-when there is so much friction that objects don’t move.
Friction def? What does it depend on?
A force that opposes motion between two surfaces that are touching.
Depends on roughness of surface, force between surface.
Gravity definition + what does it depend on?
The force of attraction between any two or more objects/substances.
Depends on the distance between the objects and the mass of each object.
How do you calculate final velocity of a falling object?
VF = 9.8 m/s/s x t
How do objects with different masses fall in a vaccum?
All objects fall at the same time because the only force acting on a object is gravity.
Air resistance definition + what does it depend on?
Friction caused by air pushing against and slowing down an object. it depends on an object’s size and shape.
Terminal velocity definition?
The highest speed a falling object can obtain. It happens when the weight of the object is equal to the air resistance.
Projectile motion definition?
When an object has both horizontal motion and vertical motion.
This means that no matter how fast an object is traveling forward, it will still fall in the same amount of time as if you dropped it.
The area around a magnet that exerts a force is called the magnetic ______
Field
Free fall def?
Free fall occurs when the only force acting on an object is gravity.
