Question

Find by drawing and by calculation the
resultant of two vectors 3 units and 4 units
inelined to each other at
a. 30°
b. 90°
c.120°​

Answer 1

Answer:

MARK ME AS BRAINLIST

Explanation:

Graphical method

1 ) Draw the two vectors to scale (with lengths of 3 and 4 units) with the correct angle between them.

2) Take a set square and a ruler. Place the set square with one edge (let’s call it “A”) along the first vector (so you can see the other vector). Place the ruler along the edge of the set square that is at right angles to the first vector.

3) Now hold the ruler stationary and slide the set square along the ruler until the edge A meets the very end of the second vector.

4) Draw a line along edge A.

Do you see that this line is parallel to the first vector?

4) Use your ruler to mark the length of the first vector along your new line.

5) now draw a line from the start of the first vector to the end of the second vector.

6) measure the angle from the first vector to this new line with a protractor. Measure the length with a ruler. This is your resultant vector angle.

Pythagoras method (use this for all right angled triangles)

The resultant vector is the hypotenuse of the triangle made from Vector 1 and 2.

We know that the square of the hypotenuse is the sum of the squares of the other two sides.

So 3^2 + 4^2 = resultant squared = 9+16 = 25

so the resultant = sqrt (25) = 5

(you can remember this 3,4,5 length of a rt angled triangle, it comes up quite a lot)

Calculation method to come.