Ch 06: Intro to Forces (Dynamics)WorksheetSee all chapters
All Chapters
Ch 01: Intro to Physics; Units
Ch 02: 1D Motion / Kinematics
Ch 03: Vectors
Ch 04: 2D Kinematics
Ch 05: Projectile Motion
Ch 06: Intro to Forces (Dynamics)
Ch 07: Friction, Inclines, Systems
Ch 08: Centripetal Forces & Gravitation
Ch 09: Work & Energy
Ch 10: Conservation of Energy
Ch 11: Momentum & Impulse
Ch 12: Rotational Kinematics
Ch 13: Rotational Inertia & Energy
Ch 14: Torque & Rotational Dynamics
Ch 15: Rotational Equilibrium
Ch 16: Angular Momentum
Ch 17: Periodic Motion
Ch 19: Waves & Sound
Ch 20: Fluid Mechanics
Ch 21: Heat and Temperature
Ch 22: Kinetic Theory of Ideal Gasses
Ch 23: The First Law of Thermodynamics
Ch 24: The Second Law of Thermodynamics
Ch 25: Electric Force & Field; Gauss' Law
Ch 26: Electric Potential
Ch 27: Capacitors & Dielectrics
Ch 28: Resistors & DC Circuits
Ch 29: Magnetic Fields and Forces
Ch 30: Sources of Magnetic Field
Ch 31: Induction and Inductance
Ch 32: Alternating Current
Ch 33: Electromagnetic Waves
Ch 34: Geometric Optics
Ch 35: Wave Optics
Ch 37: Special Relativity
Ch 38: Particle-Wave Duality
Ch 39: Atomic Structure
Ch 40: Nuclear Physics
Ch 41: Quantum Mechanics
Sections
Newton's First & Second Laws
Forces & Kinematics
Vertical Forces & Acceleration
Vertical Equilibrium & The Normal Force
Forces in 2D
Equilibrium in 2D
Newton's Third Law & Action-Reaction Pairs
Forces in Connected Systems of Objects

Concept #1: 2D Forces in Horizontal Plane

Practice: Three horizontal forces act on a box (mass = 8 kg) sitting on a smooth surface. F1 is 30 N acting at 53° counterclockwise from the +x axis, F2 is 13 N acting at 67.4° clockwise from the +x axis, and F3 is 20 N directly along the -x axis. What are the magnitude and direction of the box's acceleration?

Concept #2: Solving an Unknown 2D Force

Concept #3: 2D Forces in Horizontal and Vertical Planes

Practice: You push a 5.1kg cart along the floor with an unknown force F at 30° below the horizontal. Using a scale, you know the Normal force is 70N. What is the horizontal acceleration of the cart?

Example #1: Wind Force on a Dropped Box