PHY 222 Lecture Notes - Lecture 2: Baseball Bat, Contact Force, Friction
A force is an interaction between
2 objects
Forces casue
Acceleration (so changes in velocity and motion)
Why don't forces always cause a change?
Bc they can be canceled out by an opposite or equal force (left/right) (up/down)
Forces are measure in
Newtons
Newton (N)
1 N = 1 kg * m / s^2
2 types of forces
contact and field
contact force
A force between two objects that are touching each other. Baseball bat hitting ball, touching chair etc
non contact force
Field force ex.) gravity, Earths mass, electro static, magnetic etc
Mass
A measure of inertia that tells you a number amount of matter an object contains (mass = what is in u)
Mass is the measurement of
(Kg)the quantity of matter present in an object (protons, neutrons, electrons)
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Is mass the same everywhere? Is weight?
Mass-yes
Weight- no (changes in the moon)
Weight
The force of gravity that pulls an object to the earth( so depends on location) an object weighs less on
the moon but has the same mass on both
What is weight measured in?
Newtons (N) and Lbs
1kg on earth
10N
The moon is
1/6 the weight of Earth
A normal force is a
Perpendicular force
The force of earth formulas
Fe=gm
Fe=mg
Fg=mg
*all same thing
If a surface pushes parallel
This is friction
Friction
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find more resources at oneclass.com
Document Summary
Bc they can be canceled out by an opposite or equal force (left/right) (up/down) 1 n = 1 kg * m / s^2. 2 types of forces contact and field contact force. A force between two objects that are touching each other. Baseball bat hitting ball, touching chair etc non contact force. Field force ex. ) gravity, earths mass, electro static, magnetic etc. A measure of inertia that tells you a number amount of matter an object contains (mass = what is in u) Mass is the measurement of (kg)the quantity of matter present in an object (protons, neutrons, electrons) The force of gravity that pulls an object to the earth( so depends on location) an object weighs less on the moon but has the same mass on both. A force that opposes motion between two surfaces that are in contact (surfaces rubbing tg) pushes parallel to surface.