Motion

• An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
• Newton's second law states that if there are no external forces acting on an object, then the velocity will remain constant (i.e., the object will be moving at a steady rate). If there are external forces acting on the object, then the velocity will change according to Newton’s second law.
• Acceleration = Net Force / Mass
• The acceleration is directly proportional to the net force acting on it, and inversely proportional to its mass.
• Distance (m) = Speed × Time (s)
• For every action, there is an equal and opposite reaction.
• 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.
• A balanced force does not cause any motion or changes in speed/velocity.
• An unbalanced force causes an object to accelerate or decelerate.
• If two objects exert equal and opposite forces on one another, they will experience equal but opposite accelerations.
• Instantaneous Velocity = Average Velocity x Number Of Intervals / Time Taken To Travel That Distance
• Average Velocity = Total Distance Travelled / Number Of Intervals
• A larger net force causes a greater acceleration.
• If two objects have different masses but experience the same net force, they will both accelerate at the same rate.
• The acceleration is directly proportional to the net force applied to the object and inversely proportional to its mass.
• The United States adopted the Metric System in which length is measured in meters (m), mass is measured in kilograms (kg), and time is measured in seconds (s).
• All non-zero digits are considered to be significant in significant digits.
• Zeros that are used to hold place value hold no significance in significant digits.
• All digits in a scientific notation are significant in significant digits.
• Bohr’s model depicts Bohr’s belief that all forms of energy are quantized.
• The orbit closest to the nucleus has the least possible amount of energy for the electron.
• Kinetic energy is only gained or lost in fixed quantities.
• Electrons can jump from one orbit to another when in an excited state.
• Each orbit in the atom has a specific amount of energy.
• Any zeros that are between non-zero digits are significant in significant digits.
• Distance is a scalar measurement that measures how far an object has moved.
• Displacement is a vector quantity that measures the length and direction of the object’s movement.
• Speed is a scalar quantity that measures the rate in which an object moves.
• Velocity is a vector quantity that measures the rate and direction of motion.
• Acceleration is a vector quantity that measures the rate in change of velocity.
• If the object’s speed increases while moving, the acceleration is considered to be positive.
• If the object's velocity is constant, there is no acceleration.
• Freefall: An object in free-fall does not encounter air resistance and accelerate downwards.
• 1st Law of Motion: An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an outside force.
• Inertia: is the resistance of an object as it changes in its state of motion.
• 2nd Law of Motion: The greater the mass of the object, the more force will be required to act upon it in order to accelerate the object.
• 3rd Law of Motion: For every action force, there is an equal and opposite reaction force.
• Force: A push or a pull that is acted upon on an object that causes objects to interact.
• Force is a vector quantity that has magnitude and direction.
• When forces are balanced, there is no acceleration occurring.