Mechanics Kinematics Dynamics Mechanics Kinematics Description of how




















































- Slides: 52
Mechanics Kinematics Dynamics
Mechanics Kinematics Description of how objects move Dynamics Deals with forces and why objects move as they do
Kinematics Classical Translational Rotational Relativistic
Kinematics Translational (1 -D) x (position) v = dx/dt (velocity) a = dv/dt = d 2 x/dt 2 (acceleration)
Kinematics • Translational (3 -D):
Kinematics How are x, v, a and t related?
Kinematics How are x, v, a and t related? Consider special case with constant acceleration:
Kinematics (a = constant)
Kinematics (a = constant) Always true
Kinematics (a = constant)
Kinematics (a = constant) Always true
Kinematics (a = constant)
Kinematics (a = constant)
Kinematics How are x, v, a and t related when acceleration is NOT constant?
Kinematics How are x, v, a and t related when acceleration is NOT constant? Graphical Approach Analytical Approach
Kinematics (Graphical)
Kinematics (Graphical) Area=Velocity
Kinematics (Graphical)
Kinematics (Graphical) Positive Negative
Kinematics (Graphical)
Kinematics (Graphical) Displacement
Kinematics (Analytical)
Kinematics (Analytical) Not the answer!
Kinematics (Analytical) Do units make sense?
Kinematics (Analytical) Do limits make sense?
Kinematics (Relative Velocity) vws v. BS v. BW
Kinematics (Relative Velocity) v. SB vw. B vsw
Kinematics Classical Translational Rotational Relativistic
Kinematics (Rotational) Direction of angular velocity and angular acceleration is along the axis of rotation and can be determined by the RHR.
Kinematics (Rotational) Angular acceleration is constant
Mechanics Kinematics Dynamics
Dynamics Classical Translational Rotational Relativistic
Dynamics (Translational) Newton’s Laws
Dynamics (Newton’s Laws)
Dynamics (Translational) Conservation of Momentum
Dynamics (Translational) Impulse
Dynamics (Translational) Impulse - Graphical
Dynamics (Translational) Impulse - Graphical +Impulse -Impulse
Dynamics (Translational) Conservation of Momentum and Kinetic Energy
Dynamics Classical Translational Rotational Relativistic
Dynamics (Rotational) Torque: The CAUSE of a change in rotational motion
Dynamics (Rotational) Rotational Inertia
Dynamics (Rotational) Rotational Inertia
Dynamics (Rotational) Rotational Analog to Newton’s Laws
Dynamics (Rotational) Conservation Laws
Dynamics (Work-Energy Principle)
Dynamics (Work)
Dynamics (Conservation of Mechanical Energy)
Kepler’s Laws of Planetary Motion 1 st Law: The path of each planet about the Sun is an ellipse with the Sun at one focus. 2 nd Law: Each planet moves so that an imaginary line drawn from the Sun to the planet sweeps out equal areas in equal periods of time. 3 rd Law: (T 1/T 2)2 = (S 1/S 2)3 where T is the orbital period in years and S is the semi-major axis of the orbit in AU.
Kepler’s Laws of Planetary Motion 1 st Law: The path of each planet about the Sun is an ellipse with the Sun at one focus. Recall this empirical law was derived by Newton using the ULo. G and N 3 L. We did this by solving a general differential equation for the orbit of a particle subject to an inverse square law force.
Kepler’s Laws of Planetary Motion 2 nd Law: Each planet moves so that an imaginary line drawn from the Sun to the planet sweeps out equal areas in equal periods of time. Recall that for ALL central forces, angular momentum is conserved. Kepler’s second law is simply a consequence of the conservation of angular momentum for an inverse-square law.
Kepler’s Laws of Planetary Motion 3 rd Law: (T 1/T 2)2 = (S 1/S 2)3 where T is the orbital period in years and S is the semi-major axis of the orbit in AU. Recall that Newton’s version of Kepler’s 3 rd law generalizes to all orbiting pairs of masses and is used frequently in astronomy to determine the mass of a heavier object (planet or star) by measuring the orbital period of a much smaller object (moon, planet, artificial satellite).