Question

What is kinematics? explain!

tysm :)​

Answer 1

Kinematics, a field within mechanics, focuses on the movement of objects, independent of the forces driving that movement.

Step-by-step explanation:

Kinematics is a branch of physics that deals with the study of motion, focusing on describing and analyzing the properties of moving objects without considering the forces that cause the motion. In simpler terms, kinematics is concerned with understanding how things move and how their positions change over time. It forms the foundation for understanding more complex concepts in mechanics, which is the branch of physics that deals with the behavior of objects under the influence of forces.

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Here are some key concepts, formulas, and terminologies related to kinematics:

• Frame of Reference

Describing an object's motion involves defining its position relative to a reference frame. When setting up a position variable x, decide where to place x=0 and establish a positive direction. This choice, referred to as selecting a coordinate system or frame of reference, must remain consistent throughout your analysis. Changing coordinate systems during a calculation is not recommended, even though various frames are acceptable when used consistently.

• Displacement

The change in position of an object. It is a vector quantity, meaning it has both magnitude and direction. The formula for displacement is:

`\boxed{\left\begin{array}{ccc}\text{\underline{Displacement:}}\\ \\\Delta \vec x = x_f-x_0 \ \text{(Final position - Initial Position) }\end{array}\right }`

• Scalar and Vector Quantities

Scalar quantities have only magnitude, while vector quantities have both magnitude and direction. For instance, distance and speed are scalar quantities, whereas displacement, velocity, and acceleration are vector quantities.

• Speed and Velocity

Speed is the rate at which an object covers distance. It is a scalar quantity, meaning it has only magnitude. The formula for speed is:


`\boxed{\left\begin{array}{ccc}\text{\underline{Speed:}}\\\\Speed = \frac{\text{distance}}{\text{time}} \end{array}\right}`

Velocity is the rate of change of displacement with respect to time. It is a vector quantity, encompassing both magnitude and direction. The formula for velocity is:


`\boxed{\left\begin{array}{ccc}\text{\underline{Velocity:}}\\\\\vec v = (\Delta \vec x)/(\Delta t)\\\\\text{Where:}\\ \bullet \ \Delta \vec x \ \text{is the displacement}\\\bullet \ \Delta t \ \text{is the change in time} \end{array}\right}`

• Acceleration

Acceleration (a) is the rate of change of velocity with respect to time. It is a vector quantity. If an object's velocity changes from an initial value v_i to a final value v_f over a time interval Δt, acceleration is calculated as:


`\boxed{\left\begin{array}{ccc}\text{\underline{Acceleration:}}\\\\\vec a = (\Delta \vec v)/(\Delta t)\\\\\text{Where:}\\ \bullet \ \Delta \vec v \ \text{is the change in velocity}\\\bullet \ \Delta t \ \text{is the change in time} \end{array}\right}`

• Uniform Motion and Non-uniform Motion

Uniform motion occurs when an object covers equal distances in equal intervals of time, maintaining a constant speed. Whereas, Non-uniform motion involves varying speeds over time intervals.

• Equations of Motion

These equations relate the kinematic quantities (displacement, initial/final velocity, acceleration, and time) for an object moving with uniform acceleration. They are derived from basic calculus and are widely used in solving kinematic problems. The four equations are:

`\boxed{\left\begin{array}{ccc}\text{\underline{The 4 Kinematic Equations:}}\\\\1. \ \vec v_f=\vec v_0+\vec at\\\\2. \ \Delta \vec x=(1)/(2)(\vec v_f-\vec v_0)t\\\\3. \ \Delta \vec x=\vec v_0t+(1)/(2)\vec at^2\\\\ 4. \ \vec v_f^2=\vec v_0^2+2\vec a \Delta \vec x \end{array}\right}`

Here, v₀ represents the initial velocity, v_f represents the final velocity, a represents acceleration, Δx represents displacement, and t represents time.