(Phys110) Final Exam Flashcards
what does omega stand for in rotational kinematics and what two units can it have?
> angular velocity
rad/s and rpm
what does alpha stand for in rotational kinematics and what are its units?
> angular acceleration
rad/s^2
what does theta stand for in rotational kinematics and what two units can it have?
> angular position/displacement
rads and revs
is CCW rotation positive or negative?
positive
is CW rotation positive or negative?
negative
how do you know when acceleration is negative?
when the acceleration vector points towards the negative x or y axis
how do you know when acceleration is positive?
when the acceleration vector points towards the positive x or y axis
when is torque negative?
when the force applied causes CW rotation
when is torque positive?
when the force applied causes CCW rotation
what does r stand for in the moment of inertia equation?
the distance from the mass to the axis of rotation
what does r stand for in the torque equation?
the distance between the applied force and the pivot point
what does phi (angle) stand for in the torque equation?
the angle between the applied force and the radial line
if the problem says to find the moment of inertia about an axis that is perpendicular to the page and passes through a mass, what does the axis of rotation look like?
the axis of rotation will look like an X (denoting an out-of-page axis of rotation) on top of whichever mass it’s passing through
if the problem says to find the moment of inertia about an axis that is parallel to the plane of the image and passes through two masses, what does the axis of rotation look like?
the axis of rotation looks like a line that connects the two specified masses
what is i-hat multiplied by j-hat?
positive k-hat
what is j-hat multiplied by i-hat?
negative k-hat
what is the conservation of angular momentum?
Li = Lf
initial angular momentum = final angular momentum
when you are asked “how many revolutions…?”, what are you solving for?
> theta
angular position/displacement
initial answer will be in rads, you need to convert to revs
what is the variable for density?
rho (funky p)
what is the variable for pressure?
the letter p
what kind of area is the one in the equation: p = F/A?
cross sectional area
where is there more pressure in a container filled with liquid? at the top of a container or at the bottom?
at the bottom
where is there less pressure in a container filled with liquid? at the top of a container or at the bottom?
at the top/near the surface
what creates pressure in a container filled with liquid?
gravity