Motion and Laws of Motion

This set of vocabulary flashcards covers the fundamental concepts of motion, including distance, displacement, speed, velocity, acceleration, and Newton's equations of motion based on the lecture transcript.

Motion

A relative concept where the position of an object is changing with respect to its surroundings.

Rest

The state of an object when its position is not changing with respect to its surroundings.

Distance

The length of the actual path travelled by an object in motion while going from one point to another.

Displacement

The minimum distance between the starting and finishing points of an object's motion.

Speed

$$\text{Speed} = \frac{\text{Total distance travelled}}{\text{Time required}}$$

Velocity

The displacement that occurs in unit time, defined as $\text{Velocity} = \frac{\text{Displacement}}{\text{Time}}$.

SI Unit of speed and velocity

$$m/s$$

CGS Unit of speed and velocity

$$cm/s$$

Galileo

The first scientist to measure speed as the distance divided by time.

Uniform motion

If an object covers equal distances in equal time intervals, it is said to be moving with uniform speed.

Non-uniform motion

If an object covers unequal distances in equal time intervals, it is said to be moving with non-uniform speed.

Acceleration

The rate of change of velocity, calculated as $\text{Acceleration} = \frac{\text{Change in velocity}}{\text{Time}}$.

Uniform acceleration

When the velocity of an object changes by equal amounts in equal time intervals.

Non-uniform acceleration

When the velocity of an object changes by unequal amounts in equal time intervals.

Positive acceleration

Occurs when the velocity of an object increases; its direction is in the direction of velocity.

Negative acceleration (Deceleration)

Occurs when the velocity of an object decreases with time; its direction is opposite to the direction of velocity.

Zero acceleration

Occurs when the velocity of an object does not change with time.

Newton's First Equation of Motion

$v = u + at$, which relates velocity and time.

Newton's Second Equation of Motion

$s = ut + \frac{1}{2} at^2$, which relates displacement and time.

Newton's Third Equation of Motion

$v^2 = u^2 + 2as$, which relates displacement and velocity.

Uniform circular motion

The motion of an object along a circular path where the speed is constant, but the direction of velocity is constantly changing.