physics enriched dr. vetrone a vector quantity with the direction matching that of the velocity
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Physics Enriched
Dr. Vetrone
A vector quantity with the direction matching that of the velocity.
Which object has more momentum, why?
SI Unit: kgxm/s
Answer: The truck has more Mo bc it has more mass than the parked car.
or
or
1.
2.
Answer: The truck has more Mo bc it has a faster velocity.
How does mo of an object change if you:
a. Double it’s mass? 2mv=2P
b. Double it’s speed? m2v= 2P
c. Double mass and speed? 2m2v=4p
or
Answer: The two apples have more Mo bc they have more mass even thought the speed 4 both is the same.
When is momentum conserved in a collision?
3. Impact f and contact t are the same for both objects
t1=t2 & F1t1=F2t2
•When there is no outside force that affects the motion of the objects*
Ex: Friction, Air resistance, et+
1. Physical contact not required. (ex: electrons)
2. It is a brief force interaction between 2 masses that’s always the same F1=F2.
When’s Mo conserved in a Collision?
Total KE energy b-4 = Total KE energy after
(½ m1)(v1)sqrd. + (½ m2)(V2)sqrd. = (½m1)(v1,f)sqrd + (½ m2)(v2,f)sqrd
No heat sound or other energies are transferred. (only KE)
* No change in physical shape
Total energy of objects is not the same b4 & after collision
Some or all KE changed to heat or sound.
Stuck together or deformed.
sticky
1-D
M1V1 + M2 V2 = M1 V1f + M2V2f
P1 + P2 = P2f P2f+
2-DX Y
M1V1x + M2V2x = M1V1fx + M2V2fx
P1x + P2x = P1fx + P2fx
M1V1y + M2V2y = M1V1fy + M2V2fy
P1y+ P2y = P1fy + P2fy
P2
Acceleration greatest for least mass
(A1=F/m1) (A2= F/m2)
P1
-Is how to Mo(P)
Two things to Mo:
1. An objects ______ or ________.
2. You need impact _______ and contact __________.Force time
Speed mass
Formula:Impulse: Final Momentum – initial momentum
= impact force x contact time
3 ways to be impulsive (no repulsive)
1. Large force, long time F x t = m V
Biggest in Mo (follow throw in sports)
2. Large force, short time F x t = m v
* Big force will be needed if very short abrupt collision
2. Long time, small force
Egg doesn’t break because of extra give (time) due to the pillows