в чем разница между speed и velocity
Difference Between | Descriptive Analysis and Comparisons
Key Difference: Speed is the rate at which an object covers a distance. Velocity not only determines the speed of the object in motion but also the direction of the object in motion.
In everyday usage, the terms speed and velocity is often used interchangeably and it does not cause that much of a problem. However, when it comes to science and mathematics, these two concepts are different from each other.
In kinematics, speed is the rate at which an object covers a distance. It is a scalar quantity. Scalar means that it is used to measure the magnitude or strength of something. It has to do much with just trying to learn how much. Speed is measured using meters, kilometer, and miles per hour/per second. For air and marine travel, it is measured in knots per hour. Italian physicist Galileo Galilei is credited as being the first person to measure speed by considering the distance covered by an object. Galileo defined speed as the distance covered per unit of time.
There are two ways to measure speed: average speed or instantaneous speed. Average speed is the total distance covered over the time interval. For example: If a car covers the distance of 320 kilometers over a period of 4 hours, then the average speed would be 320km divided by 4hr, which would result in the speed being 80 km per hour. Average speed does not describe the speed variations that may have taken place during the trip such as traffic stops, reduction or acceleration in speed. Instantaneous speed is the speed that is shown on the speedometer at any given moment. If while driving, the driver looks at the speedometer, the instantaneous speed would be the speed on the meter. If a person continues to drive at that one speed for an hour, (i.e. 50 km) the speed would be considered as 50km/hr.
Velocity is the rate of change of position of an object, equivalent to a specification of its speed and direction of motion. It is a vector quantity. Velocity not only determines the speed of the object in motion but also the direction of the object in motion. In order to maintain a constant velocity, an object must travel in a certain direction for a certain amount of time. If the object changes direction, the velocity of the object also changes. The path must also not be circular or curve. An object which travels in a circle and comes back to its starting point is said to have zero velocity. For example, a car that is travelling on a circular circuit at 90 km/hr is said to have a speed of 90 km/hr, however it does not have a velocity.
Vector quantity is when an object requires both magnitude as well as direction in order to define it. The scalar absolute value (magnitude) of velocity is known as speed. So a velocity without a direction or heading is basically the speed. Another example where a car is travelling 70 km/hr in the direction north is said to have a velocity of 70 km/hr, north. Velocity is commonly used to determine the object’s speed and the direction of travel change at each point in time. The change in rate of velocity as a function of time is known as acceleration, while ‘deceleration’ is known as ‘negative acceleration’ and written with a (-) sign. Displacement plays a huge part in determine the velocity of an object. Displacement is the shortest distance from the initial to the final position of another point.
В чем разница между speed и velocity
Speed is how fast an object travels a given distance.
Velocity is the speed an object is moving at in a given direction.
The difference between speed and velocity is that velocity is speed with a direction vector associated with it. It’s that direction vector that makes them different. Let’s back up a bit and review.
Speed is displacement (distance traveled) per unit time. Velocity is displacement (distance traveled) per unit time in a given direction. The «directionallity» associated with velocity makes it a vector quantity, while speed is a scalar quantity.
The main difference between them in everyday life is that «speed» is usually used
properly, but «velocity» is usually used improperly. As you can see, «velocity» is not
just a bigger word that you can use for «speed» when you want to sound smart.
— «30 miles per hour» is a speed
— «30 miles per hour north» is a velocity
— «30 miles per hour north» and «30 miles per hour west» are the same speed but different velocities
Speed Vs Velocity: Understanding the Difference
What makes velocity different from speed?
Velocity is the rate of change of motion in a specific direction. The definition seems very simple, yet this vector quantity is complex in more ways than one.
The equation of average velocity is as follows:
Δx = position or displacement
Δt = Time interval
The line or sometimes an arrow over ν signifies that this value is a vector.
According to the equation, the value of velocity increases as the time required for displacement decreases. So, we say high velocity when the time required to cross a distance is low.
Likewise, low velocity is a result of more time required to make a displacement.
Displacement or distance
You might have noticed that we use the term displacement with velocity rather than distance. There is a reason why we chose to do so!
Distance is a scalar quantity and is a measure of the magnitude of distance covered. It is just a number that specifies how much an object has traveled from point A to point B.
Now imagine two points, separated by a distance. There are infinite ways to connect them.
The shortest distance would be a single line connecting these two points.
However, you can also connect two points using curved lines. But the distance will be different for every type of line you choose to connect the two points.
We cannot say the same for displacement because it is the measure of how far the second point is from the reference point.
Therefore, displacement has both magnitude and direction, making it a vector quality. When defining velocity, you are defining not just the rate of motion, but also its direction.
Speed vs Velocity
This is another comparison that leaves many scratching their heads. People often use the term velocity and speed interchangeably, but they both have very distinct qualities.
Let us examine the equation of speed.
There’s a striking similarity between the equation of speed and velocity. The equation tells us that speed is the rate of distance covered in a specific time frame.
But here, we are concerned only about the distance. Hence, speed is a scalar quantity that gives us the rate of motion without any information about the direction.
However, when we re-examine velocity, we can see that distance is replaced by displacement. This gives us an idea about the direction of the object.
Therefore, the velocity and speed of an object are both defined differently.
For example, let us imagine that a car travels at 20kmph. If you ask a physicist, he/she would say that the speed of the car is 20kmph but the velocity is unknown.
But if you know that the car is traveling at 20kmph to the North, then the physicist would say that the speed of the car is 20kmph and its velocity is 20kmph in the North direction.
Can the speed and velocity of an object be different?
There is always a comparison drawn between speed and velocity regarding the motion of an object. These two entities are constantly pitted against each other to see which is superior.
But there is no point comparing vector and scalar quantities because they are distinct in their ways.
To give a rough idea, consider an object traveling in a perfect circle at 20 kmph. Since this is a perfect circle and we have defined a constant rate of motion for it, speed and velocity should be the same, right?
Wrong! In this case, the speed of the object is constant, but the velocity is always changing.
This is because we consider direction when defining velocity. So when an object travels in a circle, we find that its direction is always in a state of change.
If we find out the direction of that object at any given point, it will be tangential to the outline edge of that circle.
Instantaneous Velocity and Instantaneous Speed
When we talk about the standard equation, almost always, we are talking about average speed and average velocity. However, sometimes it is necessary to know the velocity or speed at an instant.
The velocity of an object at a specific point in time is known as instantaneous velocity. The general equation for instantaneous velocity is:
The speed of an object at a specific point in time is known as instantaneous speed. The general equation for instantaneous speed is:
Where,
x = Displacement
s = Distance
The most common example of the measurement of instantaneous speed is a speedometer. Speedometers show the speed of an object in a particular instant, not its average value.
Why is velocity important?
Why bother having two equations for the rate of motion with respect to the time when you can simply use speed, which has a simpler equation?
The reason why velocity is of high importance is that, in physics, the direction of an object carries great importance.
Consider an airplane en route to its destination. To get detailed information on the airplane, air control terminals use velocity instead of the speed.
Vectors also play a very important role in helping us determine how the velocity of one object may influence another object. For example, if two objects collide in a nonlinear fashion, understanding their velocity before impact will help us understand their behavior (direction and speed) after impact.
This is not possible if you are using only the speed of the two objects. There are many more examples that you can draw when it comes to the importance of velocity in physics.
Conclusion
Velocity often gets overlooked because it doesn’t serve major roles outside of physics. However, within the realm of physics, it takes the center stage while speed is regarded with a lesser importance.
Irrespective of how important both these quantities are, understanding the differences between velocity and speed gives us great insight into the different aspects of science and its applications.
Скорость — это speed или velocity?
Часто бывает трудно перевести термины speed и velocity с учетом разницы между ними, некоторые специалисты даже считают их полными синонимами. На самом деле это не совсем так. В большинстве случаев разница в значении этих терминов не играет никакой роли. Однако бывают и такие случаи, когда просто необходимо передать оттенки различия, в противном случае теряется смысл высказывания.
Основное отличие термина velocity от термина speed заключается в том, что первый термин означает не просто скорость какого-либо процесса (например, движения), но и учитывает его направление, то есть является векторной величиной. Так, выражение to determine the target’s velocity рекомендуется перевести вариантом установить скорость движения цели в конкретном направлении, так как данная цель может двигаться в нашем направлении с одной скоростью, а в другом направлении – с другой скоростью. Кроме того, следует учитывать и тот факт, что термин velocity является больше научным термином, а термин speed не имеет строго выраженной принадлежности к какому-либо стилю. Поэтому, когда речь идет о явлениях естественнонаучного характера, а также во многих терминосочетаниях, используемых для определения скоростного параметра, применяется первый термин, например muzzle velocity (дульная скорость – область баллистики). Более того, если использовать данный термин для описания обыденных явлений, то степень проявления этих явлений усиливается. Так, в выражении the car came round the corner at such a velocity данный термин переводится не просто словом «скорость», а выражением «огромная скорость» — автомобиль свернул за угол на такой огромной скорости.
Таким образом, speed передает чистое значение величины скорости, а velocity учитывает еще и направление перемещения. При переводе на русский язык проблема возникает от того, что в русском языке имеется только один термин скорость для передачи этих двух английских терминов. Поэтому рекомендуется подбирать варианты перевода с помощью дополнительных определяющих слов, уточняющих его значение, там, где это необходимо, с учетом сказанного выше.
При переводе с русского языка рекомендуется просто запоминать конкретные устойчивые словосочетания на английском языке, поскольку в большинстве остальных случаев вариант не будет иметь особого значения.
В чем разница между speed и velocity
In simple words velocity is a more scientific word. Ex: the velocities of the emitted particles (physics)
While on the other hand speed is used more in the everyday conversations. Ex: the machine was working in a high speed.
In conclusion, velocity is speed with a direction, however speed does not have a specific direction.
Velocity is speed in a straight line. If an object is moving in a straight line it is called velocity, but if it turns while still moving, it is called speed.
Символ показывает уровень знания интересующего вас языка и вашу подготовку. Выбирая ваш уровень знания языка, вы говорите пользователям как им нужно писать, чтобы вы могли их понять.
Мне трудно понимать даже короткие ответы на данном языке.
Могу задавать простые вопросы и понимаю простые ответы.
Могу формулировать все виды общих вопросов. Понимаю ответы средней длины и сложности.
Понимаю ответы любой длины и сложности.
Решайте свои проблемы проще в приложении!
( 30 698 )