Energy and momentum - physik.uni-siegen.de · Linear momentum - Impuls. Conservation of linear...
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Energy and momentum
Transcript of Energy and momentum - physik.uni-siegen.de · Linear momentum - Impuls. Conservation of linear...
Energy and momentum
Work – kineticEnergy theorem
W= F d cos Q
Work byhorizontal movement
Work bygravitational force
W = Kf – Ki =½ mv² - ½ mv0²= F*d
Elevator capdescent
W = - m g d cos f
Work by spring force
F = - k d Hook´s law
W = ½ kxi² - ½ k xf²W < 0
W > 0
Work by a variable force
DWj = Fj Dx
Potential energy
DU = - W
Conservative force
Gravitationalpotential energy
U(y) = m g (y – yi) = m g (y – 0) = m g h
Conservativemechanical energy
K1 + U1 = K2 + U2
Potential energycurves
K(J)
0
-5
1
Energy necessary toescape
Potential energy landscape Periodic potential for electrons in a solid
bonding state
free state
Energynecessary toliberate
Linear momentum -Impuls
Conservation oflinear momentum
Inelastic collision
Elastic collision
Collision in 2D
X-axis
Y-axis
Conservation of momentum
Conservation of energy
