Torque - Lecture notes from AP Physics 1 from teacher Mr. Schmidt from a high school PDF

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Lecture notes from AP Physics 1 from teacher Mr. Schmidt from a high school in New York. Author of notes received a 5 on the ap exam and a 97 in the course. ...

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Torque ! Textbook chapter ten! ! Torque- the quantitative measure of the tendency of a force to cause or change a body's rotational motion ! ! Force is to translational motion as torque is to rotational motion ! ! τ=r(perpendicular)F=rFsinθ ! Double the radius, ! double the torque τ- torque (N•m)! F- force (N)! r- distance between F and the pivot (axle...) (m)! θ- angle between F and r (degrees) ! r(perpendicular)- "lever arm"- the perpendicular distance from F to pivot (m)! ! ! ! ! ! ! ! ! ! ! ! Example one-! ! ! ! ! ! ! ! ! ! ! Example two- ! ! ! ! ! ! ! ! ! ! ! Example three- ! !

! ! ! ! ! ! ! ! Torque continued...! ! For objects that can rotate: two possibilities ! 1. ! "Equilibrium" for systems that can rotate ! ! ! 2. ! ! ! Example one- a "light" lever (mass can be neglected): ! ! ! Where should the 250N weight be placed ! for the system to be in equilibrium? ! ! ! ! ! ! ! ! ! ! ! ! Example two- a uniform lever 4m long and weighing 200N is balanced by a force F as shown. Find F.! Uniform lever means mass is uniformly distributed The center of mass is at the center

⭐ If a uniform lever is pivoted at the center there is no torque associated with its own weight! because there is no "r-value" ! ! ! ! ! !

! Example three- two people hold a uniform lever (weight 200N) and a 400N weight as shown. ! Find F1 and F2 ! Pivot anywhere- want to chose an unknown (when ! there are two unknowns) ! ! ! ! ! ! ! ! ! ! ! ! Part two: not in equilibrium ! ! ! ! ! ! Tnet- net torque (N•m) ! I- rotational inertia (kg• m^2) ! α- angular acceleration (rad/s^2) ! ! ⭐ handy: α=a/r...