Newtonian Physics Flashcards
What is Newtonian Physics?
The description of mechanical events—those that involve forces acting on matter—using the laws of motion and gravitation
What is the definition of gravity?
A unidirectional force that pulls objects down towards earth’s center
Gravity pulls on all objects with a force of _______.
9.81 m/sec per sec (32ft/sec per sec)
Who created the law of gravity?
Sir Isaac Newton
What is the formula for gravity (be able to understand each part and what happens to the gravity force when one component is changed)?
Gravitational force= (G x m1 x m2)/d squared)?
G = Gravitational constant-(6.67 × 10−11Nm2/kg2)
m1 and m2 = masses of the two objects used to calculate force
d = distance between the centers of gravity of the two masses
Mass and weight are ______
not equivalent.
What is mass?
Mass is the total of all matter in an object—the sum of the mass of all the electrons, protons, and neutrons.
What is weight?
Weight is the total effect of gravity pulling on all the electrons, protons, and neutrons contained in an object
How is weight effected by gravitational pull?
Dependent
How is mass effected by gravitational pull?
Non dependent
Will the mass of an eraser be the same on Earth and the Moon?
Yes
Will the weight of an eraser be the same on Earth and the Moon?
No. Weight is the pull of other massive bodies on the object, and therefore does depend on the location of the object with respect to objects such as planets.
What is the formula for determining weight?
Mass x force of gravity= weight
What is the SI unit of measurement for weight?
Newton
Why do we measure our patient’s weight in kg instead of Newtons?
Because gravity is constant, we don’t need to distinguish between mass and weight
For a patient whose mass is 80 kg, what is their weight in Newtons?
Mass (kg) x Force of Gravity (9.81 m/sec2) = Weight (N)
80kg x 9.81 m/sec2 = 784.8 N
What is gravitational acceleration?
Gravity causes objects with mass to accelerate towards each other.
What two factors effect the rate of gravitational acceleration?
Mass of the objects and their proximity
Gravitational acceleration: The more mass an object contains, the _____ it will attract other objects
more
Gravitational acceleration: The closer an object is to another the _____ the attraction between them will be
greater
How does increasing object mass effect force and acceleration?
One might want to say that objects with greater mass would accelerate or be pulled faster to earth, but objects also resist movement proportional to their mass (third law of motion). Objects with greater mass are pulled by gravity with the same force and fall at the same acceleration as objects with lesser mass.
What would lead to decreased gravitational pull?
Friction-Greater friction equals greater force against the pull of gravity and slowing of a fall
What causes friction?
Air molecules possess energy, move about, and interact with other matter (friction)
Gravitational acceleration is _______ to the distance of the object to the center of the Earth
inversely proportional
How many laws of motion are there?
3
What is the first law of motion (Law of inertia)?
A body in motion tends to stay in motion unless acted upon by another force
What is the second law of motion (law of acceleration)?
Acceleration of a body is in the direction of and proportional to the force (F), and that acceleration is inversely proportional to the mass (m) of the body
What is the formula for force?
Force= mass x acceleration
If multiple forces (VECTORS) exist, the direction and acceleration are _______to the sum of all the forces
proportional
Objects with greater mass have more _______
Inertia
What is the third law of motion (law of reciprocal action)?
For every action, there is an equal and opposite reaction. Objects exert equal but opposite forces on one another
What is force?
Amount of energy required to move an object
How are the mass and force of an object relate?
Equally proportional
What is a newton?
The newton (N) is the standard measure of force derived from the force of gravity. The force required to accelerate a 1 kg weight 1 m/sec
True or false. If an object has a net force of 0 then it has no forces acting on it
False. Still forces acting on an object when net force= zero
What is the acceleration of a 1 kg mass object if you apply 1 Newton of force to it?
1 m/ms2