Week 1 Day 3

• An object in motion stays in motion (or rest) until acted upon by external force • F= m*a • for every action there is an equal and opposite reaction (picture the gun or cannon with recoil)

(kg) m = F/a amount of an object = resistance to acceleration

(m/sec) v = Âx/Ât change in location per time

(m/sec2) a = Âv/Ât change in velocity per time

(kg*m/sec2) F = m * a Push or pull needed to accelerate a mas

has magnitude and units, no direction distance, speed, mass

magnitude, units, and direction displacement, velocity, weight

(strongest force) holds protons and neutrons together in nucleus

holds electrons in atoms, tries to force protons apart

(weakest) holds earth in suns orbit and us from floating away

All matter is attracted to all other matter with the force: F = G * m1 * m2 /r2 G is the gravitational constant (a universal value) m1 and m2 are the masses of the two objects r is the distance between them.

≈9.8 m/sec2

W = m * g

mass/volume 1 ml water has mass of 1 g so the density of water is 1 g/ml

the density of a substance divided by the density of water (1g/ml) -unitless

P = F/ area ex. pounds per square inch (PSI)

Compares atmospheric pressure to a vacuum Patm = p * g * h p = density of the liquid

compares atmospheric pressure to an unknown pressure ÂP = p * g * Âh

Use expansion of bellows by pressure

Use coiled tube that “straightens” in response to pressure

(joule) kg*m2*sec2 the result of a force acting through a distance *if you push something (against a force) and it moves. W = F(N) * d (m) F= applied force N= newtons d= distance m= meters

N*m or kg * m2/sec2 measure of work

energy a mass has because it is in motion.

energy stored because of its position