Linear Kinemetics Flashcards
What is kinematics?
Kinematics is the branch of mechanics that describes the motion of objects without considering the causes of motion. It involves the description of objects moving through time and space.
Define linear motion.
Linear motion occurs when every point of an object moves the same distance, in the same direction, at the same time without any change in orientation.
What are the two types of linear motion?
The two types of linear motion are rectilinear translation (straight-line motion) and curvilinear translation (motion along a curved path).
Define angular motion.
Angular motion occurs when all points of a body or object rotate around a fixed axis, with the orientation of the object constantly changing.
What is general motion?
General motion is a combination of both linear and angular motion, such as the movement of an American football when thrown.
What is the Cartesian coordinate system?
The Cartesian coordinate system is a coordinate system that specifies each point uniquely in a plane by a pair of numerical coordinates, which are the signed distances to the point from two fixed perpendicular directed lines, measured in the same unit of length.
What is displacement?
Displacement is a vector quantity that represents the change in position of an object. It’s a straight line from the initial to the final position, with both magnitude and direction.
How do you calculate displacement using coordinates?
Displacement is the straight-line distance from an object’s initial position to its final position, with a specific direction. In a Cartesian coordinate system:
What is the difference between distance and displacement?
Distance is a scalar quantity that measures the total path length traveled by an object, regardless of direction. Displacement is a vector quantity that measures the straight-line distance from the starting point to the ending point, including direction.
Define speed and velocity.
Speed is a scalar quantity that measures how fast an object is moving, calculated as distance divided by time. Velocity is a vector quantity that measures the rate of displacement over time, including direction.
How do you calculate velocity?
Velocity is calculated by dividing displacement by time Velocity is a vector quantity that represents the rate at which an object changes its position. It is defined as the displacement over which the displacement occurs. Displacement is a vector quantity as well, which means it has both magnitude and direction.
What is velocity as a vector quantity?
Velocity is the rate of change of displacement with respect to time and includes both speed and direction. It is calculated using the formula:
velocity is distance over time.
An example from the lecture is using timing gates to measure the velocity of a sprinter by calculating the displacement between gates divided by the time taken to pass between them.
How can velocity be different even if the speed is the same?
Velocity includes direction, so two objects can have the same speed but opposite velocities if they are moving in opposite directions. For example, two cars moving at 25 meters per second in opposite directions have the same speed but different velocities, as indicated by positive and negative signs in their velocity vectors.
What is acceleration as a vector quantity?
Acceleration is the rate of change of velocity with respect to time. It is a vector quantity and can be positive (speeding up), negative (slowing down, also known as deceleration), or zero (constant velocity).
Acceleration = velocity change considering final and initial over time.
An example from the lecture is analyzing a sprinter’s ability to rapidly increase their velocity from a stationary position at the start of a race.
How does acceleration relate to changes in direction?
Since acceleration is based on velocity, which includes direction, any change in direction is considered acceleration. For instance, a car turning a corner is accelerating because its direction is changing, even if its speed remains constant.
