Physics: Forces and Motion Concepts

Balanced Forces

• Two or more forces of equal magnitude acting in opposite directions.
• An object at rest will remain motionless under balanced forces.
• Examples include a car at a constant speed, a hanging bat, and a seesaw with equal weights on each side.

Unbalanced Forces

• Unequal forces acting on an object; causing the object to move.
• An object at rest will begin to move, or an object in motion will accelerate, change speed, or direction.
• Examples include a skier speeding downhill, a frisbee gliding through the air, and a seesaw with unequal weights.

Net Force Calculations

• To calculate net force: Sum all forces acting on an object.
• Balanced Forces: Net force = 0.
• Unbalanced Forces: Net force ≠ 0.

Describing Motion

• Motion is defined as change in position relative to a reference point.
• Speed is defined as the distance traveled per unit time (rate of change in position).

Types of Speed

• Instantaneous Speed: The speed at a specific point in time.
• Average Speed: Total distance traveled divided by the total time.
• Constant Speed: Speed that remains unchanged.

Graphing Motion

• Time is represented on the X-axis.
• Distance is represented on the Y-axis.
• The slope of a distance-time graph represents an object's speed.

Distance vs Displacement

• Distance refers to the total path travelled by an object.
• Displacement is the change in position from the starting point to the ending point.
• Displacement includes both direction and magnitude, while distance only considers magnitude.

Velocity

• Velocity describes both an object's speed and direction of motion.
• Velocity changes when speed, direction, or both change.
• Velocity is calculated as displacement divided by time (V = D/T)

Acceleration

• Acceleration is the rate of change of velocity.
• Positive acceleration indicates increasing speed.
• Negative acceleration indicates decreasing speed.
• Acceleration is calculated as change in velocity divided by time (Acceleration = (Final Velocity - Initial Velocity)/Time).

Balanced Forces

• Equal forces acting in opposite directions result in no change in motion.
• Examples: A car at constant speed, a bat hanging motionless, two children of equal weight on a seesaw.

Unbalanced Forces

• Unequal forces cause a change in motion (acceleration, change in speed, or direction).
• Examples: A skier gaining speed downhill, a frisbee slowing down, two children of different weights on a seesaw.

Net Force Calculations

• Net force is the overall force acting on an object, determined by combining all forces.

Describing Motion

• Motion is a change in position relative to a reference point.
• Speed is the rate of change in position, calculated as distance traveled divided by time.
• Types of speed: Instantaneous (speed at a given moment), Average (total distance divided by total time), Constant (speed that doesn't vary).
• Graphing motion:
  • Time is plotted on the x-axis (horizontal).
  • Distance is plotted on the y-axis (vertical).
  • The slope of the line represents the speed of the object.

Distance vs Displacement

• Distance is the total length traveled.
• Displacement is the change in position from the starting point, including direction.

Velocity

• Describes both speed and direction of motion.
• A change in speed or direction, or both, results in a change in velocity.
• Calculated as displacement divided by time (Velocity = D/T).

Acceleration

• Measures the rate of change in velocity.
• Positive acceleration indicates increasing speed.
• Negative acceleration indicates decreasing speed.
• Calculated as change in velocity divided by time (Acceleration = Change in Velocity/Time).