Seatwork:
1. In your own understanding, explain Newton’s Laws of Motion.
Newton’s Laws of Motion, based on my own understanding is a law formulated by the known Isaac
Newton that primarily describes the relationship between forces acting on a body and its motion.
Three Laws were introduced. First, the Law of inertia which states that a body at rest will remain at
rest and a body in motion will remain in motion unless acted upon by an external force.
Second Law, known as the Law of acceleration simplified by the equation F=ma explains that the net
force acting on the body is equal to the product of its mass and acceleration of the body.
Newton’s Third Law or the Law of action and reaction states that in every action, there is an equal
or opposite reaction. It is applied when two bodies interact, and they apply forces to one another
which are equal in magnitude but opposite in direction.
2. In your own understanding, what is rectilinear translation, curvilinear translation, centroidal
rotation and plane motion.
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Rectilinear Translation – occurs when the body is moving along a straight path. This means
that the linear motion in which the direction of the velocity remains constant as it moves in a
straight line
Curvilinear Translation – occurs when the body is moving along a curve path and the linear
motion of the body remains parallel to the direction. An example of this is throwing a stone
into the air at an angle.
Centroidal Rotation – occurs when the motion of a body rotates in a fixed/vertical axis
through its center of gravity, but the center of gravity will remain stationary. A rotating elesi
or a turbine is one of the example.
Plane Motion- it is a combination of translation and centroidal rotation. Occurs when the
resultant of the applied single force in the system does not pass through the gravity center
and a couple combined.
3. Explain D’ Alembert’s Principles.
D’Alembert’s Principle or the Dynamic Equilibrium State, is an idea introduced by Jean Le
Rond D’ Alembert which explains that external forces acting on a rigid body are equivalent to the
effective forces of the various particles forming the body. In simple words, if the summation of
forces and product of mass and acceleration is equal to zero then the system is said to be in
equilibrium. Thus, the Equation ƩF-ma=0 and R-ma=0 is used and satisfied the stated Principle.