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Think of a screw-thread, threaded just like a screw that you might use to screw a hook into a piece of wood. In the US, all woodscrews are manufactured with what's called a "right-hand thread". That means you turn it right to go into the wood, and you turn it left to bring it out of the wood. Now keep that 'right-hand thread' in the back of your mind, and we'll look at a vector cross-product. A cross-product is the new vector you get when you operate on two vectors that you already have. You obviously know the directions of the vectors that you already have, and you're asking "What is the direction of the new vector ?". Well, call the first two vectors 'A' and 'B'. If you do the cross-product (A x B), think of that right-handed screwthread rotating from the 'A' direction to the 'B' direction. What direction did the right-hand thread advance ? That's the direction of the cross-product ! Can you picture the three-dimensional Cartesian coordinate system ? Down at the origin, where the three axes come together, if you draw three little tiny vectors down on the three axes, you'll notice that ( x cross y = z ). This will help you a lot if you ever have to draw the axes properly on a blank sheet of paper. Notice that (B x A) goes in the opposite direction of (A x B), because when you turn a right-hand thread the other way, the screw advances oppositely. Another contributor may improve this answer by describing the "Right Hand Rule", which is another, maybe better, way to get the direction of the cross product. If he is not a total genius at descriptive language, it will confuse you.
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What do you use to tell the direction?
GPS is very reliable navigation technique and is becoming common in new cars. Maps can used to find direction. Magnetic compasss can also be used to find direction.
What are the methods of adding and subtracting vector quantities?
adding vectorsTo add two vectors, s+z, simply move the vector z to the end of the vector s.subtracting vectorsTo find the magnitude and direction of the difference between two vectors, s-z, simply draw a vector from z to s
Why is something accelerating when it is traveling in a circle?
Something is accelerating when it is traveling in a circle because the direction of its velocity is changing.It is important to understand that a velocity not only has a magnitude but it also has a direction. In general, if the magnitude and/or direction of an object's velocity is changing, we say that it is accelerating.Again, if something is traveling and only the direction that it is traveling changes, we still say it is accelerating because the direction that it is traveling is changing.This is the case when something is traveling in a circle at constant speed. If you where to represent its velocity by a vector you would find that while the magnitude of the vector does not change over time, the direction of the vector does. In fact, over a very short period of time, if you where to represent the change in direction of its velocity by a vector, you would find that that "difference vector" points directly toward the center of the circle.Again, this is all a bit confusing because when we generally use the word "accelerate" we mean that something is speeding up. However one just has to get use to the idea that when something is accelerating, it may be that only the direction of its velocity is changing and not necessarily the magnitude of its velocity.To learn more about this go to the related links below.
How are scalar quantities different from vector quantities?
Vectors are quantities that have a size and a direction.Examples: Displacement, velocity, acceleration, momentum, force.Scalars are quantities that have a size but no direction.Examples: Temperature, cost, speed, length, height, width, age, energy.=====Scalar quantities have only magnitude. Vector quantities have both magnitude and direction. Temperature and volume are scalar because they don't have a particular direction.Velocity and Force (because acceleration actually has a direction) are vector quantities.Velocity is the combination of the scalar quantity of speed with a direction for that speed. Speed is always a positive number but velocity can be negative and positive because it has a direction.
How the direction of angular momentum is given by right hand rule?
Angular momentum = r x p... That is position vector r, CROSSED (not multiplied) with momentum vector p. So, to find out the direction the angular momentum will act, take ur right hand, point your fingers in the direction of r, and "curl" (close/bend whatever u wanna call it) ur FINGERS (not thumb) towards p. New, whichever way ur thumb points, that is the direction of the angular momentum Hope that helped
How do you do cross products?
You need to know that the cross product of two vectors is a vector perpendicular to both vectors. It is defined only in 3 space. The formula to find the cross product of vector a (vector a=[a1,a2,a3]) and vector b (vector b=[b1,b2,b3]) is: vector a x vector b = [a2b3-a3b2,a3b1-a1b3,a1b2-a2b1]
How to you find a vector parallel to two given vectors?
I think you meant to ask for finding a perpendicular vector, rather than parallel. If that is the case, the cross product of two non-parallel vectors will produce a vector which is perpendicular to both of them, unless they are parallel, which the cross product = 0. (a zero vector)
What is cross in science?
One type of cross is the cross or vector product of a pair of 3D vectors. If there are two unit vectors that are not parallel, their vector product is a vector that is normal to the plane containing the two vectors, so it's a good way to find that plane. In biological science, cross signifies the mating of two genotypes to produce its progeny. It may be among homozygous or heterozygous parents.
How can you find a unit vector in the same direction as the given vector?
Divide the vector by it's length (magnitude).
How do you find the magnitude and the direction of a vector?
Use trigonometry.
How do you find a vector if you have itsmagnitude and its direction given?
That's it! You know everything there is to know about it. It's not as if you have to wander through a crowd of vectors and find one that matches the description. "Find the vector" means figure out its magnitude and direction. If the problem already gave you the magnitude and direction, then it's unlikely that it's asking you to 'find' that same vector.
Find a unit vector in the direction from 3 -1 4 to 1 3 5?
find the vector<1,1>+<4,-3>
How can you find the direction of angular momentum if the position vector and force vector lie on the plane?
By finding the direction of angular velocity because it's always parallel to it.
1 For the two vectors find the scalar product AB and the vector product?
For two vectors A and B, the scalar product is A.B= -ABcos(AB), the minus sign indicates the vectors are in the same direction when angle (AB)=0; the vector product is ABsin(AB). Vectors have the rule: i^2= j^2=k^2 = ijk= -1.
How to find the area of a parallelogram with given vertices's in a 3D figure?
You need to take the magnitude of the cross-product of two position vectors. For example, if you had points A, B, C, and D, you could take the cross product of AB and BC, and then take the magnitude of the resultant vector.
How do you find a normal vector?
A normal vector is a vector that is perpendicular or orthogonal to another vector. That means the angle between them is 90 degrees which also means their dot product if zero. I will denote (a,b) to mean the vector from (0,0) to (a,b) So let' look at the case of a vector in R2 first. To make it general, call the vector, V=(a,b) and to find a vector perpendicular to v, i.e a normal vector, which we call (c,d) we need ac+bd=0 So say (a,b)=(1,0), then (c,d) could equal (0,1) since their dot product is 0 Now say (a,b)=(1,1) we need c=-d so there are an infinite number of vectors that work, say (2,-2) In fact when we had (1,0) we could have pick the vector (0,100) and it is also normal So there is always an infinite number of vectors normal to any other vector. We use the term normal because the vector is perpendicular to a surface. so now we could find a vector in Rn normal to any other. There is another way to do this using the cross product. Given two vectors in a plane, their cross product is a vector normal to that plane. Which one to use? Depends on the context and sometimes both can be used!
How do you find the magnitude and the direction of a vector when F3i-4j?
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