Q: A thin spherical planar-convex lens is surrounded by air: The lens has a radius of curvature ( R2 ) of 50mm and a refractive index ( n1 ) of 1.50. Determine the focal length. Additionally, what will happen to the lens’ focal length if it is placed within a watery medium instead of airContinue reading “GEOMETRICAL OPTICS: Focal Length and the Index of Refraction”
Author Archives: George Walker
GEOMETRICAL OPTICS: Object and Image Focal Points and Focal Lengths
When we evaluate systems that contain thin lenses, several parameters within the system may be of interest to us. At times, the distances that separate the object ( do ) and image ( di ) from a lens at hand are related to the physical dimensions of the lens itself by the Thin-Lens Equation, alsoContinue reading “GEOMETRICAL OPTICS: Object and Image Focal Points and Focal Lengths”
GEOMETRICAL OPTICS: Positive and Negative Sign Conventions
In order for the Thin-Lens Equation and similar derivations to mathematically represent thin-lens systems, sign conventions must be assigned to the physical parameters encountered within optical systems that are modeled. In some circumstances, relationships between the height of an object ( ho ) or image ( hi ) are related to the distances ( doContinue reading “GEOMETRICAL OPTICS: Positive and Negative Sign Conventions”
GEOMETRICAL OPTICS: Thin Lens Equation Derivation
Of all the various equation derivations one may encounter as an introductory physics student, the ones regarding ray diagrams are as counterintuitive as any. Whether a system at hand consists of thin lenses or mirrors, radiant energy is diagrammed as rays for the sake of simplicity. Never, ever forget that these diagrams are grossly oversimplifiedContinue reading “GEOMETRICAL OPTICS: Thin Lens Equation Derivation”
MAGNETISM AND ELECTROMAGNETISM: Lenz’ Law
Q: A loop that consists of 200 ( N ) turns and an area ( A ) of 0.25 m2 is located in a downward-directed magnetic field ( B ) of 0.40 T. Additionally, the loop’s coils have a resistance ( R ) of 5.0 Ω. If the coils are crushed to an area ofContinue reading “MAGNETISM AND ELECTROMAGNETISM: Lenz’ Law”
MAGNETISM AND ELECTROMAGNETISM: Electromagnetic Induction and the Electromotive Force ( emf )
Q: A metallic coil that consists of 200 ( N ) turns encloses an area ( A ) of 100 cm2. The coil is placed within a magnetic field ( B ) that is perpendicular to its area, and it has a magnetic flux density of 0.50 T. Next, the field is shut off, andContinue reading “MAGNETISM AND ELECTROMAGNETISM: Electromagnetic Induction and the Electromotive Force ( emf )”
MAGNETISM AND ELECTROMAGNETISM: Magnetism, Electromagnetic Induction, Lenz’s Law, and the Right-Hand Rule
Early experiments with magnetism revealed that a current-carrying wire is surrounded by circular lines of magnetic flux ( ɸ ). The orientation of this field could be predicted via usage of the Right-Hand Rule. These observations are indeed interesting, and they were made when the current ( I ) passing through a conductor was constant;Continue reading “MAGNETISM AND ELECTROMAGNETISM: Magnetism, Electromagnetic Induction, Lenz’s Law, and the Right-Hand Rule”
INTRODUCTION TO ELECTRONICS: Conventional Current, Kirchhoff’s Laws, Magnetic Fields, and the Right-Hand Rule
Conventional current refers to the convention in which electrical current ( I ) is considered to be a flow of positive charges. The usefulness of this convention is readily observable when dealing with Kirchoff’s Laws ( or Rules ) and the analysis of magnetic fields that encircle a conductor that carries a conventional current. OfContinue reading “INTRODUCTION TO ELECTRONICS: Conventional Current, Kirchhoff’s Laws, Magnetic Fields, and the Right-Hand Rule”
AP PHYSICS: Force and Deceleration
Q: A vehicle weighing ( Fw ) 17.08 kN moves at a constant velocity ( v ) of 35.8 m/s. At some point, the driver decides to let the vehicle coast in neutral, during which air drag causes it to decelerate to 22.4 m/s in 24 s. ( a ) What is the magnitude ofContinue reading “AP PHYSICS: Force and Deceleration”
KINEMATICS: Matching Equations to Appropriate Circumstances ( Part 1 )
Of all the topics that cause confusion among students new to physics, kinematics is no exception to the rule. Briefly speaking, kinematics can be described as the “ architecture of motion. “ Various types of forces ( F ) and energy ( E ) can give rise to motion observed within a system, whether thatContinue reading “KINEMATICS: Matching Equations to Appropriate Circumstances ( Part 1 )”
