Kinematics
What is the difference between a scalar and vector quantity? Provide 1 example of each.
Scalar-magnitude and unit only (distance, speed, time, temperature, mass, etc...)
Vector-magnitude, unit, and DIRECTION (displacement, velocity, acceleration, force, momentum, etc...)
In the middle of a temper tantrum, Carter charges towards a brick wall and kicks it as hard as he can. His toes are left stinging......This is an example of which law of motion?
Law #3
How much work is done if you push on a wall for an hour and a half and the wall doesn't go anywhere? Why?
In terms of physics, in order for work to be done, an object has to be displaced. In this case, the wall has not moved, so technically, you haven't done any work on the wall.
Energy is the ability to do _________________, and it is measured in _________________.
work, joules
What type of energy does a stretched rubberband contain?
Elastic Potential Energy
ACCELERATION (m/s2)
What is the difference between mass and weight? Provide 2 points.
Mass is the amount of matter an object contains. It is measured in kilograms (kg) in physics, and it does NOT depend on an object's location.
Weight is the gravitational pull of a planet on another object. It is a FORCE that is measured in Newtons (N). It DOES depend on an object's location.
Work is measured in _______________, and power is measured in _______________.
Joules, watts
The law of conservation of energy states:
Energy can NEVER be created or destroyed. It can only change forms.
What are the 3 different ways in which you can accelerate. Hint: Acceleration is a VECTOR!
1. Changing the object's speed (speeding up or slowing down), 2. Changing the object's direction, 3. Changing BOTH simultaneously
7.81 seconds
What is terminal velocity? Describe this physical phenomenon in terms of net force, acceleration, and speed.
Terminal velocity is a point that an object reaches when the object's weight is balanced out by an equal amount of wind resistance working on it. When this point is reached, the net force working on the object is 0 N, the object's acceleration is 0 m/s2, and the object continues to fall towards the ground at a constant speed.
Marco and Julie are racing up the steps. Julie is able to climb the stairs in half the time it takes Marco. Over the course of the trip, Julie has uses 30.0 watts of power. How much power has Marco used by the time he makes it?
15.0 watts
Which variable in the kinetic energy equation affects the amount of energy an object contains the most and why?
In the kinetic energy equation, the object's speed is squared, which makes it the variable that changes the amount of energy an object has the most!
What units would be used to measure the following quantities? A. Force, B. Mass, C. Work, D. Potential Energy, E. Displacement
Gary uses a slingshot to fire a paintball straight up into the air at 78.9 m/s. After 5.0 seconds of travel, what is the stones speed?
29.9 m/s
An object is experiencing zero newtons of net force. The two possible scenarios for an object in this case would be......
1) The object could be at REST, or 2) The object could be moving at a constant speed!
The power rating of an electric weed eater is 2,282 watts. If the weed eater is used for 6.00 seconds, how many joules of work were done by the weed eater?
13,700 joules
An object sitting on top of a 5.00 meter tall shelf has 100. joules of potential energy. If the same object were moving at a speed of 60.0 m/s, how much kinetic energy would the object have?
3690 Joules
Reaction Force= Windshield hitting the bug.
On a position vs. time graph, a flat, horizontal line tells you that the object is_____________________, while a flat, horizontal line on a speed vs. time graph tells you that the object is_____________________.
AT REST, MOVING AT A CONSTANT SPEED
A skydiver is falling towards the ground. If the skydiver weighs 602 N, and there is a 242 newton resistance force working on him as he falls, what is the net force working on the skydiver? DON'T FORGET THAT FORCE IS A VECTOR!
360 Newtons of force towards the ground
If 377 watts of power is used, what is the power of this object in terms of horsepower?
.505 hp
Before jumping off of a diving board, Wendy (30.0 kg) has 50,000. joules of potential energy. After 5.00 seconds of falling, she now only has 13,985 joules of potential energy. At this 5.00 second mark, how much kinetic energy does she have?
36,015 Joules
Rearrange the kinetic energy equation for speed. KE=1/2mv2
The square root of 2 x kinetic energy/m.