Unit 3 - Gravity and Kinetic Energy

These flashcards cover key concepts related to gravity, kinetic energy, acceleration, and the relationships between mass and weight, as outlined in the study guide.

Speed

How fast something moves, calculated as distance divided by time.

Acceleration

A change in speed, which can occur by speeding up, slowing down, or changing direction.

Gravity

The force that causes a constant acceleration of approximately 9.8 m/s² for falling objects.

Weight

The force of gravity acting on an object, calculated as mass times gravity.

Mass

The amount of matter in an object, measured in kilograms (kg), which does not change regardless of location.

Potential Energy (PE)

Stored energy due to an object's height, calculated using the formula PE = mgh.

Kinetic Energy (KE)

The energy of motion, calculated with the formula KE = ½mv².

Negative acceleration

A decrease in speed, also known as deceleration or slowing down.

Position vs. time graph - Steeper line

Indicates a faster speed.

Position vs. time graph - Straight line

Indicates a constant speed.

Position vs. time graph - Curved line

Indicates acceleration.

Relationship between mass and falling objects

Objects with different masses, when ignoring air resistance, fall at the same rate.

Energy changes when falling

Potential energy decreases while kinetic energy increases as an object falls.

Common mistake regarding mass and weight

Mass does not equal weight; heavier objects do not fall faster.

Speed

How fast something moves, calculated as distance divided by time.

Acceleration

A change in speed, which can occur by speeding up, slowing down, or changing direction.

Gravity

The force that causes a constant acceleration of approximately 9.8\ m/s^{2} for falling objects.

Weight

The force of gravity acting on an object, calculated as mass times gravity.

Mass

The amount of matter in an object, measured in kilograms (kg), which does not change regardless of location.

Potential Energy (PE)

Stored energy due to an object's height, calculated using the formula PE = mgh.

Kinetic Energy (KE)

The energy of motion, calculated with the formula KE = \frac{1}{2}mv^{2}.

Negative acceleration

A decrease in speed, also known as deceleration or slowing down.

Position vs. time graph - Steeper line

Indicates a faster speed.

Position vs. time graph - Straight line

Indicates a constant speed.

Position vs. time graph - Curved line

Indicates acceleration.

Relationship between mass and falling objects

Objects with different masses, when ignoring air resistance, fall at the same rate.

Energy changes when falling

Potential energy decreases while kinetic energy increases as an object falls.

Common mistake regarding mass and weight

Mass does not equal weight; heavier objects do not fall faster.

Velocity

The speed of an object in a specific direction; it is a vector quantity.

Displacement

The change in position of an object, measured in a straight line from the starting point to the ending point.

Force

A push or pull on an object resulting from its interaction with another object, measured in Newtons (N).

Newton's First Law (Law of Inertia)

An object at rest stays at rest, and an object in motion stays in motion with the same speed and direction unless acted upon by an unbalanced force.

Newton's Second Law

The acceleration of an object is dependent upon the net force acting upon the object and the mass of the object (F = ma).

Friction

A force that opposes the motion of an object when it is in contact with another surface or fluid.

Work

The transfer of energy that occurs when a force is applied over a distance (W = Fd), measured in Joules (J).

Power

The rate at which work is done or energy is transformed (P = \frac{W}{t}), measured in Watts (W).

Law of Conservation of Energy

Energy cannot be created or destroyed, only transformed from one form to another, such as from Potential Energy to Kinetic Energy.