Physics Final Exam Flashcards
Explain the difference between a scalar quantity and a vector quantity.
Scalar quantity uses the measurement of magnitude.
Example: Speed, time
Vector quantity uses the measurement of magnitude and direction
Example: Displacement
Einstein
Light travels in waves
Light moves at a constant speed
Galileo
Corrected Aristotle’s ideas
Discovered traits about acceleration, and the acceleration due to gravity on Earth is 9.8 m/s/s
Kepler
Found that planets move in elliptical paths around the sun
Takes longer to orbit the sun when farther away
Newton
Discovered the three laws of motion as they apply on Earth
Aristotle
Found that his 3 laws of motion were NOT accurate.
Is it possible to have a negative acceleration?
Yes, acceleration is based on velocity and time and you could be decelerating, like in a car, so that would be a negative acceleration.
Acceleration = V/t
Is it possible to have a negative velocity? Why, or why not?
Yes, velocity includes both speed and direction. A negative velocity indicates motion in the opposite direction to a chosen reference point of a positive direction.
Is it possible to have a negative speed? Why, or why not?
No, speed is always positive or zero because it only measures how fast an object is moving, not its direction
As I sit in a chair the chair puts force up on me.
Action and Reaction (3rd
As I swim…I push the water backwards, my body moves forwards.
3rd (Aciton/Reaction)
When I kick a soccer ball…if I had more force the ball leaves with greater acceleration.
F=ma (2nd Law of Newtons Three)
In race cars engineers do their best to keep the mass low, with greater force I will have greater acceleration
2nd (F=ma)
As a golfer accelerate the golf club down into the swing it strikes the ball with more force, which allows the ball to travel a farther distance.
2nd (F= ma)
When a car stops suddenly the passengers move forward until they hit the dash, or the seat belt stops them.
1st (Inertia)
When I turn off the ceiling fan, the blades continue to move until they run out of energy.
1st (Inertia)
A softball player hits a ball between the CF and LF. The ball continues to roll until it hits the fence.
1st Law of Motion
The forces that we learned about are…applied force, air resistance, gravity, friction, spring force (compression/tension), normal force, electrical force, magnetic force, buoyancy. Explain how the force is present and explain the additional forces that affect that force.
Applied Force: somone is applying force to a table to push it across the room. Force of a person pushing, force of table.
Friction Force: softball players force from running and sliding on the gravel, force of player upward force of ground.
Air resistance: force of the object and the air, force of airplane with air
Gravity Force: an object falling off a table and landings on the floor. Force of object falling, upward force of ground stopping it.
What type of friction?
A soccer ball rolling across the field.
Rolling Friction
What type of friction?
A piece of wood being pulled across a table
Sliding Friction
What type of friction?
A book resting on a table, not moving.
Static Friction
What type of friction?
A diver going through the water into a pool.
Fluid Friction
Your own example…of friction
A softball player sliding into home; sliding friction.
Gravity is the Earth’s force pulling at you to keep you close to Earth. Agree, disagree? Explain
Agree, gravity is the interaction and attraction between 2 objects that have mass. It depends on the mass and the distance between the objects of 2 centers to determine the force of gravity. The closer we are to the Earth’s center, the stronger the pull of gravity. If we were further away, that pull would weaken.
Law of Conservation of momentum.
The object with greater mass is moving at a slower velocity, while the object with lesser mass is moving at a faster velocity. Both objects have the same momentum, even with differences in mass and velocity. Two different-sized vehicles, with different velocities, are going at the same speed.
