Components that a Vector

Vectors room geometric representations of magnitude and also direction and can it is in expressed together arrows in two or 3 dimensions.

You are watching: Can magnitude of a vector be negative

Key Takeaways

Key PointsVectors can be broken down into two components: magnitude and also direction.By acquisition the vector to be analyzed as the hypotenuse, the horizontal and vertical components can be uncovered by completing a ideal triangle. The bottom leaf of the triangle is the horizontal component and also the side opposite the edge is the upright component.The angle the the vector renders with the horizontal have the right to be used to calculation the length of the 2 components.Key Termscoordinates: numbers indicating a position with respect to part axis. Ex: \textx and also \texty collaborates indicate position relative come \textx and \texty axes.axis: An imaginary line roughly which things spins or is symmetrically arranged.magnitude: A number assigned to a vector denote its length.


Vectors are geometric representations of magnitude and also direction which are regularly represented by straight arrows, starting at one allude on a name: coordinates axis and ending in ~ a various point. Every vectors have a length, called the magnitude, which to represent some top quality of attention so the the vector might be compared to an additional vector. Vectors, gift arrows, likewise have a direction. This differentiates them from scalars, which are mere numbers without a direction.

A vector is characterized by that is magnitude and also its orientation with respect come a collection of coordinates. That is often useful in analyzing vectors to break them into their ingredient parts. For two-dimensional vectors, these components are horizontal and also vertical. For 3 dimensional vectors, the magnitude component is the same, yet the direction component is expressed in regards to \textx, \texty and also \textz.

Decomposing a Vector

To visualize the process of decomposing a vector into its components, begin by drawing the vector from the origin of a set of coordinates. Next, attract a right line native the beginning along the x-axis till the heat is even with the guideline of the initial vector. This is the horizontal ingredient of the vector. To uncover the vertical component, draw a line right up from the finish of the horizontal vector until you reach the guideline of the initial vector. Girlfriend should discover you have actually a right triangle such the the original vector is the hypotenuse.

Decomposing a vector into horizontal and vertical contents is a an extremely useful method in knowledge physics problems. Whenever you see motion at an angle, you have to think of that as relocating horizontally and vertically in ~ the very same time. Simple vectors in this means can rate calculations and aid to store track that the motion of objects.

Components of a Vector: The initial vector, characterized relative to a set of axes. The horizontal component stretches from the begin of the vector to its the furthest x-coordinate. The upright component stretches from the x-axis come the most vertical suggest on the vector. Together, the two components and also the vector type a best triangle.


A Vector: an instance of a vector. Vectors room usually represented by arrows with their length representing the magnitude and their direction represented by the direction the arrowhead points.

Vectors need both a magnitude and also a direction. The size of a vector is a number for comparing one vector to another. In the geometric translate of a vector the vector is stood for by an arrow. The arrow has two components that define it. The two parts are its length which represents the magnitude and its direction with respect come some collection of name: coordinates axes. The greater the magnitude, the longer the arrow. Physical concepts such as displacement, velocity, and acceleration room all examples of amounts that have the right to be represented by vectors. Each of this quantities has both a magnitude (how far or how fast) and also a direction. In order to specify a direction, there must be something come which the direction is relative. Commonly this reference suggest is a collection of name: coordinates axes favor the x-y plane.

Scalars differ from vectors in the they execute not have a direction. Scalars are used generally to stand for physical quantities for which a direction does no make sense. Some instances of these are: mass, height, length, volume, and area. Talking about the direction of these quantities has actually no an interpretation and therefore they cannot be expressed together vectors.

Key Takeaways

Key PointsTo add vectors, lay the very first one on a collection of axes through its tail in ~ the origin. Place the next vector v its tail in ~ the ahead vector’s head. As soon as there are no much more vectors, draw a straight line native the origin to the head that the last vector. This line is the sum of the vectors.To subtract vectors, continue as if including the two vectors, however flip the vector to be subtracted throughout the axes and then sign up with it tail come head as if adding.Adding or individually any variety of vectors yields a result vector.Key Termsorigin: The facility of a name: coordinates axis, characterized as gift the name: coordinates 0 in every axes.Coordinate axes: A collection of perpendicular lines which define coordinates relative to an origin. Example: x and y coordinate axes define horizontal and also vertical position.

Adding and also Subtracting Vectors

One the the ways in i m sorry representing physical amounts as vectors makes analysis easier is the ease through which vectors might be added to one another. Due to the fact that vectors space graphical visualizations, addition and subtraction of vectors can be done graphically.

The graphical method of vector enhancement is also known together the head-to-tail method. Come start, draw a set of coordinate axes. Next, draw out the very first vector through its tail (base) at the beginning of the coordinate axes. Because that vector enhancement it go not matter which vector you draw an initial since enhancement is commutative, but for individually ensure that the vector friend draw an initial is the one you room subtracting from. The next step is to take it the next vector and also draw it such the its tail starts in ~ the vault vector’s head (the arrow side). Continue to location each vector in ~ the head of the preceding one until all the vectors you great to add are joined together. Finally, draw a right line indigenous the beginning to the head the the final vector in the chain. This new line is the vector result of adding those vectors together.

Graphical enhancement of Vectors: The head-to-tail technique of vector enhancement requires the you lay the end the first vector along a collection of name: coordinates axes. Next, place the tail that the following vector on the head the the an initial one. Attract a new vector from the beginning to the head the the last vector. This new vector is the amount of the original two.

Vector v Horizontal and also Vertical Components: The vector in this image has actually a size of 10.3 units and a direction of 29.1 degrees over the x-axis. It have the right to be decomposed right into a horizontal part and a vertical component as shown.

For example, a vector v a length of 5 in ~ a 36.9 level angle come the horizontal axis will have actually a horizontal component of 4 units and also a upright component that 3 units. If we were to add this to another vector of the very same magnitude and direction, us would acquire a vector twice as long at the very same angle. This can be viewed by including the horizontal materials of the two vectors (4+4) and also the 2 vertical components (3+3). These enhancements give a brand-new vector with a horizontal ingredient of 8 (4+4) and also a upright component that 6 (3+3). To discover the result vector, simply ar the tail of the upright component at the head (arrow side) of the horizontal component and then attract a line from the beginning to the head of the vertical component. This new line is the result vector. It should be twice as long as the original, since both the its components are double as huge as they to be previously.

To subtract vectors through components, simply subtract the two horizontal contents from each other and do the exact same for the upright components. Then attract the resultant vector together you did in the ahead part.

Key Takeaways

Key PointsA vector is a amount with both magnitude and also direction.A scalar is a amount with just magnitude.Multiplying a vector by a scalar is equivalent to multiplying the vector’s size by the scalar. The vector lengthens or shrinks but does not readjust direction.Key Termsvector: A command quantity, one through both magnitude and also direction; the in between two points.magnitude: A number assigned come a vector denote its length.scalar: A quantity that has magnitude however not direction; to compare vector.


Although vectors and scalars stand for different varieties of physics quantities, it is sometimes important for them come interact. While including a scalar come a vector is impossible since of their various dimensions in space, the is possible to multiply a vector by a scalar. A scalar, however, can not be multiply by a vector.

To multiply a vector through a scalar, merely multiply the comparable components, the is, the vector’s size by the scalar’s magnitude. This will an outcome in a new vector v the same direction however the product the the 2 magnitudes.


For example, if you have a vector A through a certain magnitude and also direction, multiply it through a scalar a through magnitude 0.5 will give a new vector v a size of fifty percent the original. Likewise if you take it the number 3 which is a pure and unit-less scalar and also multiply it come a vector, you get a version of the original vector i m sorry is 3 times together long. As a more physical instance take the gravitational force on an object. The force is a vector through its magnitude depending upon the scalar well-known as mass and also its direction gift down. If the massive of the thing is doubled, the force of heaviness is doubled as well.

Multiplying vectors by scalars is very useful in physics. Most of the units offered in vector amounts are intrinsically scalars multiply by the vector. For example, the unit of meters per 2nd used in velocity, i beg your pardon is a vector, is made up of 2 scalars, which space magnitudes: the scalar of size in meters and the scalar that time in seconds. In order to do this conversion from magnitudes come velocity, one have to multiply the unit vector in a specific direction by these scalars.

Scalar Multiplication: (i) multiply the vector \textA through the scalar \texta=0.5 yields the vector \textB which is half as long. (ii) multiplying the vector \textA through 3 triples the length. (iii) copy the massive (scalar) doubles the pressure (vector) the gravity.

Scalar Multiplication: (i) multiplying the vector A through 0.5 halves that is length. (ii) multiply the vector A through 3 triples that length. (iii) enhancing the massive (scalar) increases the force (vector).

When multiplying a vector by a scalar, the direction that the vector is unchanged and also the magnitude is multiply by the size of the scalar. This outcomes in a brand-new vector arrow pointing in the very same direction as the old one but with a much longer or much shorter length. You can also attain scalar multiplication with the use of a vector’s components. As soon as you have the vector’s components, multiply each of the materials by the scalar to obtain the new components and also thus the new vector.

A valuable concept in the study of vectors and geometry is the principle of a unit vector. A unit vector is a vector through a length or magnitude of one. The unit vectors are different for various coordinates. In Cartesian works with the directions room x and y commonly denoted \hat\textx and \hat\texty. V the triangle above the letters described as a “hat”. The unit vectors in Cartesian collaborates describe a circle recognized as the “unit circle” which has actually radius one. This have the right to be seen by acquisition all the possible vectors of size one at every the possible angles in this name: coordinates system and placing lock on the coordinates. If you were to attract a line approximately connecting every the top of all the vectors together, you would obtain a one of radius one.

Position, Displacement, Velocity, and also Acceleration together Vectors

Position, displacement, velocity, and also acceleration have the right to all be displayed vectors due to the fact that they are defined in terms of a magnitude and also a direction.

Learning Objectives

Examine the applications the vectors in evaluating physical quantities

Key Takeaways

Key PointsVectors space arrows consist of of a magnitude and a direction. They are supplied in physics to represent physical quantities that also have both magnitude and also direction.Displacement is a physics term an interpretation the street of things from a referral point. Due to the fact that the displacement has two pieces of information: the distance from the reference suggest and the direction far from the point, the is well stood for by a vector.Velocity is defined as the rate of adjust in time of the displacement. To recognize the velocity of things one must know both how fast the displacement is changing and in what direction. Thus it is also well represented by a vector.Acceleration, gift the price of adjust of velocity also requires both a magnitude and also a direction family member to some coordinates.When illustration vectors, you often do not have enough room to attract them come the range they are representing, so the is necessary to represent somewhere what range they are being attracted at.Key Termsvelocity: The rate of adjust of displacement v respect to change in time.displacement: The length and also direction of a right line in between two objects.acceleration: the rate at which the velocity of a body changes with time

Use that Vectors

Vectors can be used to stand for physical quantities. Most frequently in physics, vectors are used to represent displacement, velocity, and acceleration. Vectors room a mix of magnitude and direction, and are attracted as arrows. The size represents the magnitude and the direction of that amount is the direction in which the vector is pointing. Due to the fact that vectors are built this way, it is valuable to analysis physical quantities (with both size and direction) as vectors.


In physics, vectors are useful due to the fact that they have the right to visually represent position, displacement, velocity and also acceleration. When drawing vectors, you frequently do not have actually enough an are to attract them come the scale they room representing, so it is important to represent somewhere what scale they room being attracted at. Because that example, when drawing a vector that represents a magnitude of 100, one may draw a line that is 5 units lengthy at a scale of \displaystyle \frac120. Once the train station of the scale is multiply by the drawn magnitude, it have to equal the really magnitude.

Position and Displacement

Displacement is characterized as the distance, in any direction, of an item relative to the place of another object. Physicists use the ide of a position vector as a graphical device to visualize displacements. A place vector expresses the place of an item from the origin of a name: coordinates system. A place vector can additionally be provided to display the place of things in relationship to a reference point, an additional object or initial place (if examining how far the object has actually moved from its initial location). The place vector is a straight line attracted from the arbitrary origin to the object. When drawn, the vector has actually a length and also a direction relative to the coordinate system used.


Velocity is additionally defined in regards to a magnitude and direction. Come say that something is obtaining or losing velocity one must additionally say how much and in what direction. Because that example, an aircraft flying at 200 \frac\textkm\texth to the northeast can be stood for by one vector pointing in the northeast direction through a magnitude of 200 \frac\textkm\texth. In drawing the vector, the magnitude is only essential as a way to compare two vectors the the exact same units. So, if there to be another airplane flying 100 \frac\textkm\texth come the southwest, the vector arrow should be half as long and also pointing in the direction the southwest.


Acceleration, being the time rate of adjust of velocity, is created of a magnitude and a direction, and also is drawn with the same ide as a velocity vector. A worth for acceleration would not be useful in physics if the magnitude and also direction that this acceleration to be unknown, i m sorry is why these vectors are important. In a complimentary body diagram, because that example, of an object falling, it would be useful to usage an acceleration vector close to the thing to signify its acceleration towards the ground. If gravity is the only force acting on the object, this vector would certainly be pointing downward v a size of 9.81 \frac\textm\texts^2 the 32.2 \frac\textft\texts^2.

See more: How Many Phone Numbers Are Possible, Wrong Number ( Real World )

Vector Diagram: here is a guy walking up a hill. His direction of take trip is characterized by the angle theta family member to the vertical axis and also by the length of the arrowhead going increase the hill. The is additionally being accelerated downward by gravity.