Physics Reviewer PDF
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This document is a reviewer/notes on general physics topics, including scientific notation, accuracy, systematic errors, vector addition and projectile motion. It explains key concepts with examples and formulas. There is no indication of an exam.
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REVIEWER IN GENERAL PHYSICS 1 Scientific Notation Definition: A way to express very large or small numbers. Example: The correct form of scientific notation is 5.367×10-35 Accuracy vs Precision Accuracy: How close a measurement is...
REVIEWER IN GENERAL PHYSICS 1 Scientific Notation Definition: A way to express very large or small numbers. Example: The correct form of scientific notation is 5.367×10-35 Accuracy vs Precision Accuracy: How close a measurement is to the true value. For example, hitting the goal (not just the goal post). Precision: How consistent repeated measurements are. Key Fact: Precise measurements can be inaccurate, but accurate measurements are not necessarily precise. Systematic Errors Definition: Consistent errors due to flaws in instruments or procedures. Example: An uncalibrated balance can cause systematic errors. Random vs Systematic Errors Random Errors: Unpredictable errors that affect precision. Systematic Errors: Consistent errors that affect accuracy. Adding Vectors Definition: Vectors have both magnitude and direction. Same Direction: Add the magnitudes directly. Key Concept: The sum of two vectors in the same direction is their total magnitude. Vector Addition Methods Graphical Method: Add vectors by drawing them head-to-tail and measuring the resultant vector. Algebraic Method: Add magnitudes and use trigonometry (sine, cosine, or tangent) to find direction. Adding Opposite Vectors If two vectors of equal magnitude but opposite directions are added, the resultant magnitude is zero. Resultant Vector Calculation When adding perpendicular vectors, use the Pythagorean theorem to find the magnitude, and trigonometry to find the direction. Constant Velocity Key Concept: If an object moves at a constant velocity, its acceleration is zero. Free Fall Acceleration Objects in free fall near Earth's surface experience constant acceleration of 9.8 m/s 2 downward. Calculating Acceleration Formula: a=Δv/Δt For example, if a velocity changes from 0 to 20 m/s in 5 seconds, the acceleration is 4 m/s 2 Negative Slope on Velocity-Time Graph A negative slope indicates the object is slowing down. Velocity-Time Graph Interpretation A straight line with a negative slope means the car is decelerating (slowing down). Accelerating vs Constant Speed Car A, which is accelerating, will eventually pass Car B, which is moving at a constant speed. Projectile Motion Definition: The motion of an object in two dimensions under gravity. Key Concept: Objects in projectile motion move in a parabolic path. Vertical Velocity at the Highest Point: Always zero. Vertical Velocity in Projectile Motion At the highest point, the vertical velocity is zero. Projectile Motion Components Horizontal Velocity: Stays constant in the absence of air resistance. Vertical Velocity: Changes due to gravity. Range in Projectile Motion The range is the total horizontal distance the projectile travels. Constant Horizontal Velocity in Projectile Motion The horizontal component remains constant because gravity only affects vertical motion. Trajectory of a Horizontally Thrown Object The path is a parabolic curve due to gravity pulling it downward. Projectile Motion Calculations Time of flight and maximum height can be calculated using kinematic equations and trigonometry for projectiles. Projectile Launch Angle 30° Launch: Greater horizontal distance. 60° Launch: Greater maximum height. Horizontal vs Dropped Ball Both balls hit the ground at the same time, assuming no air resistance. Forces in Circular Motion Centripetal Force: The force that keeps an object moving in a circular path. It points towards the center of the circle. Centrifugal Force: Not a real force, but a result of inertia acting outward in a rotating frame. Circular Motion Objects in circular motion constantly change direction due to centripetal force, which acts towards the center. “Don’t watch the clock. Do what it keeps. Keep going”.