10TH GRADE · DYNAMICS

Newton's laws

Relationship between forces and acceleration and interaction of bodies.

20 minutes8 theory cards

LESSON MATERIAL

Basic Concepts

The property of a body to maintain a state of rest or uniform linear motion in the absence of a resultant force.

No force is needed to maintain uniform motion. A resultant force is needed to change the speed of a body.

Basic laws of dynamics that connect the movement of a body with the forces acting on it.

In the problem, you need to select the body, show the acting forces and add them as vectors: it is the resultant that determines the acceleration.

LESSON MATERIAL

F

A measure of the mechanical interaction of bodies.

Unit: newton · $\mathrm{N}$

\sum F

The vector sum of all forces acting on a body.

Unit: newton · $\mathrm{N}$

LESSON MATERIAL

F=ma

The resultant force is equal to the product of mass and acceleration.

1\,\mathrm{N}=1\,\frac{\mathrm{kg}\cdot\mathrm{m}}{\mathrm{s}^2}

One Newton gives a mass of one kilogram an acceleration of one meter per second squared.

\sum\vec{F}=m\vec{a}

The vector sum of forces is equal to the product of mass and acceleration.

\vec{F_1}=-\vec{F_2}

The forces of interaction between two bodies are equal in magnitude and opposite in direction.

PRACTICE