Answer:
F = 7.2N
Explanation:
The resultant of two forces acting at some angle is given by using the vector addition as given below
F =√F1^2+F2^2+2F1F2cosθ
Where F1 = 6N and F2 = 8N
θ = 240°
Substituting the values into the equation above
F = √ 6^2+8^2+ 2(6×8)cos240
F =√ 36+64+96cos240
F = √ 100+96 ×-0.5
F = √ 100-48
F = √ 52
F = 7.211
F = 7.2N
Take east to be the positive direction. Then the resultant force from adding <em>F</em>₁ and <em>F</em>₂ is
<em>F</em>₁ + <em>F</em>₂ = (-45 N) + 63 N = 18 N
which is positive, so it's directed east.
To this we add a third force <em>F</em>₃ such that the resultant is 12 N pointing west, making it negative, so that
18 N + <em>F</em>₃ = -12 N
<em>F</em>₃ = -30 N
So <em>F</em>₃ has a magnitude of 30 N and points west.
Plate tectonics<span>is a </span>scientific theory<span> that describes the large-scale motion of </span>Earth<span>'s </span>lithosphere<span>. This theoretical model builds on the concept of </span>continental drift<span> which was developed during the first few decades of the 20th century. The </span>geoscientific<span> community accepted plate-tectonic theory after </span>seafloor spreading was validated in the late 1950s and early 1960s.<span>The lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken up into </span>tectonic plates<span>. </span>
Do you have a book about it? or if you have a dictionary?
