GENERAL PHYSICS II Math. Edu. Program. Yohanes Edi Gunanto TC - UPH. Concept of Force and Newton’s Laws of Motion. Forces. Gravitation Electric and magnetic forces Elastic forces (Hooke’s Law) Frictional forces: static and kinetic friction, fluid resistance
GENERAL PHYSICS IIMath. Edu. Program
Yohanes Edi Gunanto
TC - UPH
Concept of Force and Newton’s Laws of Motion
Electric and magnetic forces
Elastic forces (Hooke’s Law)
Frictional forces: static and kinetic friction,
Contact forces: normal forces and static friction
Tension and compression
Every body continues in its state of rest, or ofuniform motion in a right line, unless it iscompelled to change that state by forcesimpressed upon it.
Use coordinate system as a ‘reference frame’ to describe the position, velocity, and acceleration of objects.
Newton’s First Law in relatively inertial referenceframes: If there is no net force impressed on anobject at rest in Frame 2, then there is also nonet force impressed on the object in Frame 1.
An object that is at rest in Frame 2 is moving at aconstant velocity in reference Frame 1.
Near the surface of the earth, the gravitational interaction between a body and the earth is mutually attractive and has a magnitude of
where mgrav is the gravitational mass of the body and g is a positive constant.
Consider two textbooks that are resting one on top of the other. The lower book has M2and is resting on a nearly frictionless surface. The upper book has mass M1 < M2. Suppose the coefficient of static friction between the books is μs.
A horizontal force of magnitude F is applied to the lower book so that the two books move together without slipping. Identify all action-reaction pairs of forces in this problem and draw free-body force diagrams on each object.
Varies in direction and magnitude depending on applied forces :
Static friction is equal to it’s maximum value
Application of Newton’sSecond Law
Newton’s Laws of Motion:
• Words, Force Diagrams, Equations
• Force Laws: contact, spring, universalgravity, uniform gravity, drag.
ΣF = ma
• Origin and Type of forces, Vectors
Two blocks 1 and 2 of mass m1and m2respectively are attached by a string wrapped around two pulleys as shown in the figure. Block 1 is accelerating to the right on a fricitonless surface. You may assume that the string is massless and inextensible and that the pulleys are massless. Find the accelerations of the blocks and the tension in the string connecting the blocks.
Technique: Separation of Variables: The acceleration is