ECAT Pre General Science Mathematics Chapter 24 Vectors

• 
  A
• 
  B
• 
  C
• none of these D

If a +b +c =0 then which of the following is true

• a =b =c =0 A
• a,b =b,c =c,a B
• a xb=b xc =c xa C
• None D

If a,b,c are unit vectors then |a + b|2 +|a - b|2

• 4 A
• 8ab B
• 9cos C
• 4(a,b) D

Which of the following is a vector

• length A
• momentum B
• volume C
• speed D

• 
  A
• 
  B
• 
  C
• 
  D

The physical quantity which possesses both magnitude and direction is called a

• scalar A
• vector B
• constant C
• none of these D

Which of the vectors have opposite direction?

• 
  A
• 
  B
• 
  C
• 
  D

The zero vector is regarded to be parallel to

• Every vector A
• Is some cases B
• Both a,b C
• None D

• 0 A
• 1 B
• -1 C
• None D

If the angle between two vectors with magnitude 2 and 15 is 30°then their scalar product is

• 
  A
• 15 B
• 30 C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

The unit vector along x-axis is

• 
  A
• 
  B
• 
  C
• none of these D

• 
  A
• 
  B
• 
  C
• 
  D

• 0 A
• 1 B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

A vector with magnitude one is called

• constant vector A
• unit vector B
• zero vector C
• null vector D

Which of the following is a vector.

• distance A
• temperature B
• energy C
• acceleration D

The zero vector is

• [0, 0, 0] A
• [1, 1, 1] B
• [0, 1, 0] C
• [0, 0, 1] D

• 
  A
• 
  B
• 
  C
• none of these D

• 
  A
• 
  B
• 
  C
• 
  D

If a,b,c are three non-coplanar vector then [a +b,b +c,c +a] = _____

• [a.b.c] A
• 2[a,b,c] B
• [abc]-2 C
• 2[abc]2 D

• 
  A
• 
  B
• 
  C
• 
  D

If a force F = 2i + j +3k acts at point (1,-2,2) of a body then the moment of F about a pint lying on the line of action of the force is

• 5 A
• Equal to the moment of the force about origin B
• 0 C
• Cannot be found D

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• none of these D

If a,b c are sides of a triangle taken in order then a x b =

• b x c A
• b x a B
• cxa C
• Both a & b D

• Free vector A
• Null vector B
• Unit vector C
• None of these D

If θ be angle between u,v and u,v determine the sides of a triangle then the third side opposite to angle θ has length

• |u+v| A
• |u|+|v| B
• |u-v| C
• |u|-|v| D

The ortho center of triangle whose vertices are (0,0)(3,0)(0,4) is

• (0,0) A
• (1,1) B
• (2,2) C
• (3,3) D

• l²+ m²+ n²= 0 A
• l² - m²+ n²= 1 B
• l²+ m²+ n²= 1 C
• l²+ m²- n²= 0 D