Forces and Motion

• Newton's first law of motion states that an object at rest will stay at rest, and an object in motion will stay in motion with the same speed and direction, unless acted upon by an external force.
• For every action, there is an equal and opposite reaction.
• Inertia is the tendency of an object to resist changes in motion.
• The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
• Newton's first law states that if there are no forces acting on an object, it will continue to move at constant velocity or remain stationary.
• The force on an object is the product of its mass and acceleration.
• Speed = Distance / Time
• Newton's third law of motion states that for every action, there is an equal and opposite reaction.
• Free fall refers to objects falling under the influence of gravity alone without any other forces acting on them.
• The acceleration due to gravity on Earth is approximately 9.8 m/s^2.
• The acceleration produced by a constant force acting on a mass depends only on the magnitude of the force and the mass of the object being moved.
• A change in velocity requires a net force to act on it.
• Weight is the gravitational pull acting on an object.
• A vector quantity has both magnitude (size) and direction.
• Mass is the amount of matter in an object.
• An example of a scalar quantity is temperature or time.
• An example of a vector quantity is velocity or displacement.
• A vector quantity has both magnitude (size) and direction, while a scalar quantity only has magnitude.
• An example of a vector quantity is displacement, which can be represented using arrows pointing in different directions.
• Vector quantities have units such as meters per second (m/s), newtons (N), kilogram-meters squared per second (kg m^2 s^-1), and joules (J).
• Force can be calculated using F = ma, where F is the force, m is the mass, and a is the acceleration.
• Velocity = Speed x Direction (m/s)
• Acceleration = Change in Velocity / Time (m/s^2)
• Distance = Average speed x time taken (m)
• Velocity = Speed x Direction
• Acceleration = Change in Velocity / Time Taken
• Accelerated free fall occurs when an object falls with an initial upward velocity due to being thrown into the air.
• Terminal velocity is reached when the downward pull of gravity equals the upward thrust from air resistance.
• An unbalanced force causes an object to change its speed, direction, or both.
• Instantaneous velocity is the rate at which an object changes position over very short intervals of time.
• A balanced force does not cause an object to change its speed or direction.
• Average speed can be calculated using distance traveled divided by time taken.
• Friction opposes relative movement between two surfaces in contact.
• Inertia is the tendency of an object at rest to remain at rest or an object moving with uniform speed to continue doing so unless acted upon by an external unbalanced force.
• Friction is a contact force between two surfaces that opposes relative movement between those surfaces.
• Newton's first law states that if there are no resultant forces acting on an object, its velocity will remain unchanged or continue at a constant rate.
• If an object is moving with a constant velocity, this means that the sum of all external forces acting on the object equals zero.
• If a force acts on an object, it causes a change in motion or results in a new state of rest.
• Acceleration is the rate at which an object changes its velocity.
• The SI unit for mass is kilograms (kg).