In the first part of his journey he traveled 40 m and in the second part he traveled 30 m. This gives us a total distance traveled of 40 m + 30 m = 70 m.
The man's resultant displacement is the
vector from where he started to where he ended. It is the vector sum of his two separate displacements. We will use the head-to-tail method of accurate construction to find this vector.
A scale of 1 cm represents 10 m (1 cm = 10 m) is a good choice here. Now we can begin the process of construction.
We draw the first displacement as an arrow 4 cm long in an eastwards direction.
Starting from the head of the first vector we draw the second vector as an arrow 3 cm long in a northerly direction.
Now we connect the starting point to the end point and
measure the length and direction of this arrow (the resultant).
To find the direction you measure the angle between the resultant and the 40 m vector. You should get about 37
.
Finally we use the scale to convert the length of the resultant in
the scale diagram to the actual magnitude of the resultantdisplacement. According to the chosen scale 1 cm = 10 m. Therefore 5 cm represents 50 m. The resultant displacement is then 50 m 37
north of east.
The
parallelogram method is another graphical technique of finding the resultant of two vectors.
Method: The Parallelogram Method
Make a rough sketch of the vector diagram.
Choose a scale and a reference direction.
Choose either of the vectors to be added and draw it as an arrow
of the correct length in the correct direction.
Draw the second vector as an arrow of the correct length in the
correct direction from the tail of the first vector.
Complete the parallelogram formed by these two vectors.
The resultant is then the diagonal of the parallelogram. The
magnitude can be determined from the length of its arrow using thescale. The direction too can be determined from the scale diagram.
A force of
is applied to a block in a horizontal direction. A second force
is applied to the object at an angle of 30
above the horizontal.
Determine the resultant force acting on the block using the
parallelogram method of accurate construction.
In this problem a scale of 1 cm = 1 N would be appropriate, since then the vector diagram would take up a reasonable fraction of the page. We can now begin the accurate scale diagram.
Let us draw
first. According to the scale it has length
5 cm.
Next we draw
. According to the scale it has length 4 cm. We make use of a protractor to draw this vector at 30
to the horizontal.
Next we complete the parallelogram and draw the diagonal.
The resultant has a measured length of 8,7 cm.
We use a protractor to measure the angle between the horizontal and the resultant. We get 13,3
.
Finally we use the scale to convert the measured length into the
actual magnitude. Since 1 cm = 1 N, 8,7 cm represents 8,7 N. Therefore the resultant force is 8,7 N at 13,3
above the horizontal.
if three forces F1.f2 .f3 act at a point on a Cartesian plane in the daigram .....so if the question says write down the x and y components ..... I really don't understand
a fixed gas of a mass is held at standard pressure temperature of 15 degrees Celsius .Calculate the temperature of the gas in Celsius if the pressure is changed to 2×10 to the power 4