Dynamics: Normal & Tension Forces 🚠 - SAT Physics Learning & Test Prep
May 6, 2020·3 min
The episode begins by defining dynamics as the study of forces that cause motion, distinguishing between contact and non-contact forces. Contact forces, including friction, air resistance, tension, and normal force, are explained as resulting from electrostatic repulsion between atoms. Non-contact forces like gravity are mentioned briefly. The normal force is detailed for objects on flat surfaces, where it equals weight (n = w), and on inclined planes, where it equals the perpendicular component of weight (n = w cos θ). Tension is introduced as a pulling force along flexible media such as ropes. Hooke's law is presented with the equation f = kx, where k is stiffness and x is extension, describing a proportional relationship up to the elastic limit. The episode notes that this relationship is linear on force-extension graphs and applies only within elastic limits. Elasticity is defined as the ability to return to zero extension when load is removed. The elastic limit is identified as the maximum sustainable force for this return. The content is delivered in an educational tone without guests, focusing on foundational physics concepts for test preparation.
