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PHXI04:MOTION IN A PLANE

361798 If \(\vec A = 2\hat i + 4\hat j - 5\hat k\) the direction of cosines of the vector \({\vec A}\) are

1 \(\frac{1}{{\sqrt {45} }},\,\frac{2}{{\sqrt {45} }}\,\,{\rm{and}}\,\,\frac{3}{{\sqrt {45} }}\)

2 \(\frac{2}{{\sqrt {45} }},\,\frac{4}{{\sqrt {45} }}\,\,{\rm{and}}\,\,\frac{{ - 5}}{{\sqrt {45} }}\)

3 \(\frac{3}{{\sqrt {45} }},\,\frac{2}{{\sqrt {45} }}{\rm{, }}\,{\rm{and}}\,\,\frac{5}{{\sqrt {45} }}\)

4 \(\frac{4}{{\sqrt {45} }}{\rm{,0 }}\,{\rm{and}}\,\,\frac{4}{{\sqrt {45} }}\)

PHXI04:MOTION IN A PLANE

361799 The vector projection of a vector \(3\hat i + 4\hat k\) on \(y\)-axis is

1 \(4\)

2 \(5\)

3 \({\rm{Zero}}\)

4 \(3\)

PHXI04:MOTION IN A PLANE

361798 If \(\vec A = 2\hat i + 4\hat j - 5\hat k\) the direction of cosines of the vector \({\vec A}\) are

1 \(\frac{1}{{\sqrt {45} }},\,\frac{2}{{\sqrt {45} }}\,\,{\rm{and}}\,\,\frac{3}{{\sqrt {45} }}\)

2 \(\frac{2}{{\sqrt {45} }},\,\frac{4}{{\sqrt {45} }}\,\,{\rm{and}}\,\,\frac{{ - 5}}{{\sqrt {45} }}\)

3 \(\frac{3}{{\sqrt {45} }},\,\frac{2}{{\sqrt {45} }}{\rm{, }}\,{\rm{and}}\,\,\frac{5}{{\sqrt {45} }}\)

4 \(\frac{4}{{\sqrt {45} }}{\rm{,0 }}\,{\rm{and}}\,\,\frac{4}{{\sqrt {45} }}\)

PHXI04:MOTION IN A PLANE

361799 The vector projection of a vector \(3\hat i + 4\hat k\) on \(y\)-axis is

1 \(4\)

2 \(5\)

3 \({\rm{Zero}}\)

4 \(3\)