What is the area of the triangle whose vertices are \((0, 7, 10)\), \((-1, 6, 6)\) and \((-4, 9, 6)\)?
\(9\) square units
Taking the vertices as \(A(0,7,10)\), \(B(-1,6,6)\), \(C(-4,9,6)\), the vectors \(\vec{AB}=(-1,-1,-4)\) and \(\vec{AC}=(-4,2,-4)\) give \(\vec{AB}\times\vec{AC}=(12,12,-6)\), whose magnitude is \(\sqrt{144+144+36}=18\). The area of the triangle is half this magnitude, that is, \(9\) square units.
A spacecraft located at î + 2ĵ + 3k̂ is subjected to a force λ k̂ by firing a rocket. The spacecraft is subjected to a moment of magnitude
Two adjacent sides of a parallelogram are 2î - 4ĵ + 5k̂ and î - 2ĵ - 3k̂. What is the magnitude of dot product of vectors which represent its diagonals?
ABCD is a quadrilateral whose diagonals are AC and BD. Which one of the following is correct?
What is the area of the parallelogram having diagonals 3î + ĵ - 2k̂ and î - 3ĵ + 4k̂?
The area of the square, one of whose diagonals is 3î + 4ĵ is
ABCD is a parallelogram and P is the point of intersection of the diagonals. If O is the origin, then \(\overrightarrow {{\rm{OA}}} + \overrightarrow {{\rm{OB}}} + \overrightarrow {{\rm{OC}}} + \overrightarrow {{\rm{OD}}} \) is equal to
The adjacent sides of AB and AC of a triangle ABC are represented by the vectors -2i + 3j + 2k and -4i + 5j + 2k respectively. The area of the triangle ABC is
A force \(\vec F = 3\hat i + 4\;\hat j - 3\;\hat k\) is applied at the point P, whose position vector is \(\vec r = 2\hat i - 2\hat j - 3\hat k\) . What is the magnitude of the moment of the force about the origin?
A force \(\vec F = 3\hat i + 2\hat j - 4\hat k\) is applied at the point (1, -1, 2). What is the moment of the force about the point (2, -1, 3)?
Let ABCD be a parallelogram whose diagonals intersect at P and let O be the origin. What is \(\overrightarrow {{\rm{OA}}} + \overrightarrow {{\rm{OB}}} + \overrightarrow {{\rm{OC}}} + \overrightarrow {{\rm{OD}}}\) equal to?
A spacecraft located at î + 2ĵ + 3k̂ is subjected to a force λ k̂ by firing a rocket. The spacecraft is subjected to a moment of magnitude
A force of 78 grams acts at the point (2, 3, 5), the direction ratios of the line of action being 2, 2, 1. The magnitude of its moment about the line joining the origin to the point (12, 3, 4) is:
Let \(\rm \vec{a}\), \(\rm \vec{b}\) and \(\rm \vec{c}\) be the position vectors of the three vertices A, B, C of a triangle respectively. Then the area of this triangle is given by:
Forces 3î + 2ĵ + 5k̂ and 2î + ĵ - 3k̂ are acting on a particle and displace it from the point 2î - ĵ - 3k̂ to the point 4î - 3ĵ + 7k̂. The work done by the force is:
Constant forces \(\rm \vec P\) = 2î - 5ĵ + 6k̂ and \(\rm \vec Q\) = -î + 2ĵ - k̂ act on a particle. The work done when the particle is displaced from A whose position vector is 4î - 3ĵ - 2k̂, to B whose position vector is 6î + ĵ - 3k̂, is: