Glossary

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Glossary

Glossary

angular velocity
ωω size 12{ω} {}, the rate of change of the angle with which an object moves on a circular path
arc length
ΔsΔs size 12{Δs} {}, the distance traveled by an object along a circular path
banked curve
the curve in a road that is sloping in a manner that helps a vehicle negotiate the curve
center of mass
the point where the entire mass of an object can be thought to be concentrated
centrifugal force
a fictitious force that tends to throw an object off when the object is rotating in a non-inertial frame of reference
centripetal acceleration
the acceleration of an object moving in a circle, directed toward the center
centripetal force
any net force causing uniform circular motion
Coriolis force
the fictitious force causing the apparent deflection of moving objects when viewed in a rotating frame of reference
fictitious force
a force having no physical origin
gravitational constant, G
a proportionality factor used in the equation for Newton's universal law of gravitation; it is a universal constant—that is, it is thought to be the same everywhere in the universe
ideal angle
the angle at which a car can turn safely on a steep curve, which is in proportion to the ideal speed
ideal banking
the sloping of a curve in a road, where the angle of the slope allows the vehicle to negotiate the curve at a certain speed without the aid of friction between the tires and the road; the net external force on the vehicle equals the horizontal centripetal force in the absence of friction
ideal speed
the maximum safe speed at which a vehicle can turn on a curve without the aid of friction between the tire and the road
microgravity
an environment in which the apparent net acceleration of a body is small compared with that produced by Earth at its surface
Newton's universal law of gravitation
every particle in the universe attracts every other particle with a force along a line joining them; the force is directly proportional to the product of their masses and inversely proportional to the square of the distance between them
non-inertial frame of reference
an accelerated frame of reference
pit
a tiny indentation on the spiral track moulded into the top of the polycarbonate layer of CD
radians
a unit of angle measurement
radius of curvature
radius of a circular path
rotation angle
the ratio of the arc length to the radius of curvature on a circular path

Δ θ = Δs r Δ θ = Δs r size 12{Δθ= { {Δs} over {r} } } {}

ultracentrifuge
a centrifuge optimized for spinning a rotor at very high speeds
uniform circular motion
the motion of an object in a circular path at constant speed