Also known as displacement change rate.
It can be defined as the change of displacement of a moving object in unit time. The size is equal to the distance traveled by an object in unit time.
Or defined as: in physics, the speed of physical movement is expressed by the ratio of displacement to the time taken for such displacement to occur.
Speed is a vector with magnitude and direction. Velocity is numerically equal to the displacement of the object in unit time, and the direction of velocity is the direction of the object's movement.
The unit of speed is the composite unit of length unit and time unit, which is meters per second (m/s) in the international system of units.
Often
Centimeter per second (cm/s)
Kilometer/hour (kilometer/hour)
Michael, miles per hour (miles
One; one
Hours)
Calculation formula: v=δx/δt
V stands for speed
Δ x represents displacement.
Δ t represents the time taken through the displacement.
The word "speed" is a physical quantity that describes the direction and position of an object, and speed can only explain the motion state of the object, but not others.
Speed reflects the speed of movement, and the word "speed" is also extended to language to express the speed of development and change of things.
The fastest speed is the speed of light in vacuum.
Speed is the ratio of the distance △s traveled by a moving object to the time △t spent traveling this distance. That is, (s 1-s0)/(t 1-t0)
Speed is a scalar, which only describes the speed of an object and does not reflect its direction.
What is speed? What does speed mean?
This rate is the number of frames that can be transmitted by the digital camera built in the video conference product within 1 sec. Because the pixel of camera sensor used in video conference system is not very high, the current rate is between 15 frames/sec and 30 frames/sec, which is enough to meet the demand of video conference products.
Acceleration is the ratio of the speed change to the time taken for this change. It is a physical quantity that describes the speed change of an object, usually expressed as a, and the unit is meters per second. Acceleration is a vector, its direction is the same as the direction of external force, its direction indicates the direction of speed change, and its size indicates the size of speed change. The acceleration is different in different parts of the earth. Newton's second law of kinematics holds that a=f/m,
F is the external force on the object, and m is the mass of the object. Force is the condition to change the motion state of an object, and acceleration is the physical quantity to describe the motion state of an object. There is no necessary relationship between acceleration and speed. When the acceleration is large, the speed can be small, and when the speed is large, the acceleration can also be small. From the differential point of view, acceleration is the derivative of velocity with respect to time and the slope in V-T image. When the acceleration and speed are in the same straight line, the object moves in a variable-speed linear motion, such as the car starts with constant acceleration (uniform acceleration linear motion) and simple harmonic motion (variable acceleration linear motion); When the acceleration and velocity directions are not in the same straight line, the object moves in a variable speed curve, such as flat throwing motion (uniform acceleration curve motion) and uniform circular motion (variable acceleration curve motion); When the acceleration is zero, the object is stationary or moving in a straight line at a uniform speed. Any complex motion can be regarded as the synthesis of numerous uniform linear motions and uniform acceleration motions.
Popular supplement:
The car was stationary before it started. The speed of the car after starting is 100 km/h, so what is the process of the speed at rest from zero to 100 km/h? Then there is the acceleration when the speed of the object increases. If the speed of the object increases, it means that the acceleration is greater than zero, that is, it is accelerating; On the contrary, the speed of the object is decreasing, indicating that the acceleration is less than zero and the object is decelerating.
Formula:
Use v0 to indicate the speed at the beginning of an object (initial speed), vt to indicate the speed at the end of a period of time (final speed), and vt-v0 to indicate the acceleration, then:
a=(vt-v0)/t