**Dynamics - Forces:**

**Misconceptions:**

**A force is the amount of energy it takes to move an object.****An object at rest does not have any forces acting on it.**

**Proper Conceptions:**

**A force is a push or a pull.**

**An object at rest has a net force of zero; however, there can be multiple forces acting on the object equal in magnitude but opposite in direction.**

Misconceptions:

Misconceptions:

**Inertia is directly related to the mass and motion of an object.****Objects in motion have a net force acting on them.**

**Proper Conceptions:**

**Inertia is directly related to mass.****If an object is moving at constant velocity, the net force acting on the body is zero.**

Misconceptions:

Misconceptions:

**The magnitude of the velocity must be increasing or decreasing for an object to be accelerating.****The force of gravity is zero if you are standing on a planet because the distance between you and the planet is zero.****Acceleration due to gravity (g) is always equal to -9.8 m/s2**

**Proper Conceptions:**

**Objects moving in a circular path will have the same magnitude of velocity; however, the object is constantly changing directions.****The force of gravity is NOT zero as the distance measured is from the center of the planet to the surface (i.e. radius).****Acceleration due to gravity (g) is different and this is dependent upon the mass and radius of the planet or body.**

**Kinematics:**

Misconceptions:

Misconceptions:

**Motion in the x and y dimensions are not independent of each other.**

**Proper Conceptions:**

**Motion in the x and y dimensions are independent of each other. The only force affecting the projectile is the force of gravity.**

**Misconceptions:**

**If the slope of a position versus time graph is not zero but is linear, then the acceleration is not zero.**

**Proper Conceptions:**

The slope of a position versus time graph is not zero but is linear then the velocity is constant (not changing) and therefore the acceleration is zero.

Misconceptions:

The slope of a position versus time graph is not zero but is linear then the velocity is constant (not changing) and therefore the acceleration is zero.

Misconceptions:

**Objects in motion are accelerating.****The direction of acceleration is always in the same direction as the velocity.**

**Proper Conceptions:**

**Objects in motion have velocity or speed but not necessarily acceleration.****If the acceleration vector is in the opposite direction of the velocity vector the object is slowing down. If the acceleration and velocity vectors are pointed in the same direction the object is speeding up.**