Speed, Velocity, and Acceleration
What is distance/time?
Speed
What is net force? Which unit is it measured in?
It is the overall force which is exerted on an object, and it is measured in Newtons (N).
What are Newton's three laws of motion in their order?
The 1st Law - An object at rest will remain at rest and an object in motion will remain in motion until acted upon by an unbalanced force. (Law of inertia)
The 2nd Law - The force of an object is equal to its mass multiplied by its acceleration. (Law of acceleration)
The 3rd Law - For every action there is an equal and opposite reaction. (Law of action and reaction)
What is the formula for work? Name all units.
Work (J, joules) = Force (N, newtons) × Distance (m, meter)
What is energy?
Energy is the ability to do work.
What is speed with respect to direction?
Velocity
What net force do balanced forces have? Do they change the position of an object?
They have a net force of 0 N because they cancel each other out; thus, they do not change the position of an object.
A truck with a mass of 6000 kg and a car with a mass of 1500 kg are moving with the same amount of force. Which vehicle will have more acceleration?
The car, which has less mass. (F = ma can be modified to F/m = a; if F stays the same, as m increases, a decreases)
Is a person pushing a box doing work?
Yes
What is the difference between potential and kinetic energy?
Potential energy is stored energy, while kinetic energy is the energy in motion.
What is a change in velocity which is usually measured in m/s2 called?
Acceleration
What are unbalanced forces?
They are forces that cause a change in the position of the object they are exerting force on and have a positive net force.
What is the difference between a distance vs. time graph and a speed vs. time graph?
Distance vs. time graphs are used to calculate speed, while speed vs. time graphs are used to calculate acceleration.
Is a person holding a box doing work?
No
What is the Law of Conservation of Energy?
The Law of Conservation of Energy states that energy cannot be created or destroyed, but it can be converted.
What is the velocity of a car which goes 3600 kilometers in 40 hours backwards? (Answer in m/s for 250 extra points)
90 km/h or 25 m/s
What is the net force exerted on an object with forces of 15 N and 40 N moving it right and a force of 60 N moving it left? In which direction will the object move?
The object will have a net force of 5 N moving left.
What is displacement?
Displacement is how far an object is away from where it started.
How much work does a person do if they push a cart with a mass of 30 kg across 10 meters with a force of 40 N?
400 J
List the forms of energy.
Mechanical energy, Radiant energy, Chemical energy, Electrical energy, Nuclear energy, Thermal energy, and Sound energy (MR. CENTS)
What is the acceleration of a ball which has an initial velocity of 20 m/s and a final velocity of 0 m/s over the course of 40 seconds?
-0.5 m/s2
Forces of 15 N and 98 N are pushing left on an object, while forces of 53 N and 60 N are pushing right on the object. What is the net force exerted on the object, and are the forces balanced or unbalanced?
The forces are balanced with a net force of 0 N.
If a person walked 8 m down a street, turned a 90° corner, then walked 15 m, what is their displacement?
17 m (using Pythagorean theorem)
How much force does a person put into pushing a box 12 meters if they do 396 J of work?
33 N
Where can all energy on Earth be traced back to?
The Sun