Find the Magnitude and the Direction (Unit Vetors)

In summary, the conversation is about a student who missed their physics class and needs help understanding questions about adding and subtracting unit vectors and calculating their magnitudes and directions. They also request a diagram for clarification. The conversation ends with a suggestion to use component notation to solve the given equations.
  • #1
sugar1
3
0
Hi,

I missed the first lecture of my physics class and need help answering these simple questions. They have to do with adding and subtraction and multiplying unit vectiors. What do they mean by direction, this is in degrees?

Also, I am not sure if this is possible but a diagram would be very helpful.

Homework Statement



Suppose B = -7i + 2j and G=6i - 4j. Find the magnitude and direction of:

a.) B + G
b.) B - G
c.) 3B

Thank you
 
Physics news on Phys.org
  • #2
Do you have a textbook for your class? It will show you how to add and subtract vectors, calculate their magnitudes, and find unit vectors.
 
  • #3
sugar1 said:
Hi,

I missed the first lecture of my physics class and need help answering these simple questions. They have to do with adding and subtraction and multiplying unit vectiors. What do they mean by direction, this is in degrees?

Also, I am not sure if this is possible but a diagram would be very helpful.

Homework Statement



Suppose B = -7i + 2j and G=6i - 4j. Find the magnitude and direction of:

a.) B + G
b.) B - G
c.) 3B

Thank you
Can you determine at least what B+ G, B- G, and 3B are? The point of "component notation" is that you can deal with the corresponding components separately:
(ai+ bj)+ (ci+ dj)= (a+c)i+ (b+d)j, 3(ai+ bj)= 3ai+ 3bj.
 

1. What is the difference between magnitude and direction in vector quantities?

The magnitude of a vector is its size or length, while the direction refers to the angle at which the vector points. Magnitude is a scalar quantity, meaning it only has a numerical value, whereas direction is a vector quantity since it has both magnitude and direction.

2. How do you find the magnitude of a vector?

To find the magnitude of a vector, you can use the Pythagorean theorem, which states that the square of the length of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides. In other words, the magnitude is the square root of the sum of the squares of the vector's components.

3. What are unit vectors and how are they used?

Unit vectors are vectors with a magnitude of 1 and are typically used to represent the direction of a vector. They are useful because they do not change the magnitude of a vector when multiplied by a scalar. Unit vectors are also used to represent the basis vectors of a coordinate system.

4. How do you represent the direction of a vector using unit vectors?

To represent the direction of a vector using unit vectors, you can break the vector into its x, y, and z components and then multiply each component by its respective unit vector (i, j, k for x, y, z). The resulting sum will be a unit vector pointing in the same direction as the original vector.

5. Can the magnitude of a vector be negative?

No, the magnitude of a vector is always a positive value. It represents the size or length of the vector and cannot be negative. However, the direction of a vector can be positive or negative, depending on the angle at which it points.

Similar threads

Finding the magnitude (length) and direction (angle) of a vector
    • Introductory Physics Homework Help
Replies
2
Views
581
Find a unit vector for a particular vector
    • Calculus and Beyond Homework Help
Replies
6
Views
2K
Intuition on the direction of friction in a rotational dynamics problem
    • Introductory Physics Homework Help
Replies
13
Views
1K
Magnitude, Unit vectors,unknown variables
    • Calculus and Beyond Homework Help
Replies
10
Views
5K
Find unit vetors satisfying qualifying conditions HELP test tomorrow
    • Calculus and Beyond Homework Help
Replies
3
Views
7K
Calculate the magnitude and direction of the torque
    • Introductory Physics Homework Help
Replies
1
Views
2K
To find the magnitude of the resultant of forces around a triangle
    • Introductory Physics Homework Help
Replies
4
Views
1K
Electrostatics? Magnitude and direction of a magnetic field
    • Introductory Physics Homework Help
Replies
4
Views
1K
Magnitude of directional and gradient vectors?
    • Calculus and Beyond Homework Help
Replies
3
Views
2K
How do you find the normal unit vector to a parametric curve?
    • Calculus and Beyond Homework Help
Replies
4
Views
2K

Hot Threads

Recent Insights

Back
Top