7TH GRADE · POWERS
Strength, heaviness and body weight
Force as a measure of interaction, heaviness, weight and weightlessness.
The entire theory of the lesson is collected here; you can read it without an account. In interactive mode, the same theory appears as cards, followed by questions. with checking the answer and task, and progress is saved.
Basic Concepts
Force
A vector physical quantity that is a measure of the interaction of bodies and can change the movement or deform the body.
For force, the meaning, direction and point of application are important; One newton is the SI unit of force.
Gravity
The force of attraction of a body by a celestial body, directed near the surface vertically to its center.
On another planet, the same mass remains the same, but the force of gravity changes along with the acceleration of gravity.
Weight and weightlessness
Weight is the force exerted by the body on a support or suspension, and weightlessness means the absence of such action.
The weight may differ from the force of gravity during accelerated movement, and in free fall the support is not loaded.
Physical quantities
Force
A quantitative measure of the mechanical interaction of bodies.
Unit: newton ·
Gravity
The force of attraction of a body by a planet near its surface.
Unit: newton ·
Weight
The force exerted by a body on a support or suspension.
Unit: newton ·
Acceleration of free fall
Acceleration of a body in free fall at a given location.
Unit: meters per second squared ·
Lesson formulas
Gravity at the surface
The force of gravity is equal to the product of mass and the acceleration of gravity.
Related formulas
The same formulas in the reference, with symbols and units.
Tasks on the topic
Statements, answer options and the walkthrough.