Introduction To Three Dimensional Geometry CBSE Questions & Answers

Introduction To Three Dimensional Geometry

This is Mathematics Class 11 Introduction to Three Dimensional Geometry CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
The lines
  • A
    perpendicular
    Correct
  • B
    parallel
  • C
    skew
  • D
    coincident
2
The line x = 1 , y = 2 is
  • A
    lies in a plane parallel to XY – plane
  • B
    parallel to X – axs
  • C
    parallel to Z – axs
    Correct
  • D
    parallel to Y – axs
3
The equation ( x – 1 ) ( x – 2 ) = 0 represents , in three dimensional space , a
  • A
    sphere
  • B
    pair of parallel planes
    Correct
  • C
    pair of straight lines
  • D
    an empty set
4
A point ( x , y , z ) moves parallel to X- axis . Which of the three variables x , y , z remain fixed ?
  • A
    z and x
  • B
    x and y
  • C
    x
  • D
    y and z
    Correct
5
A point ( x , y , z ) moves parallel to XY - plane . Which of the three variables x , y , z remain fixed ?
  • A
    x
  • B
    z
    Correct
  • C
    x and y
  • D
    y
6
The plane x = 0 divides the join of ( - 2 , 3 , 4 ) in the ratio
  • A
    it is 2 : 1
    Correct
  • B
    it is - 4 : 3
  • C
    it is 3 : 2
  • D
    it is 1: 2
7
The direction cosines of the line joining ( 1 , - 1 , 1 ) , and ( -1 , 1 , 1 ) are
  • A
    \(<\) 2 , - 2 , 0 \(>\)
  • B
    \(<\) 1 , - 1 , 0 \(>\)
  • C
    \(<\) \({1 \over {\sqrt 2 }}, - {1 \over {\sqrt {2} }},0 > \)
    Correct
  • D
    \(<\) 1 , - 1 , 1 \(>\)
8
The line \({{x - {x_1}} \over 0} = {{y - {y_1}} \over 1} = {{z - {z_1}} \over 2}\) is
  • A
    none of these
  • B
    at right angles to plane YOZ
  • C
    is parallel to Y- axis
  • D
    at right angles to x –axis
    Correct
9
The line \(x = {x_1},y = {y_1}\) is
  • A
    none of these
  • B
    parallel to z axis
    Correct
  • C
    parallel to x axis
  • D
    parallel to y axis
10
Skew lines are
  • A
    coplanar lines
  • B
    none of these
    Correct
  • C
    intersecting lines
  • D
    parallel lines
11
The locus of the equation xy + yz = 0 is
  • A
    a pair of parallel planes
  • B
    none of these
  • C
    a pair of straight lines
  • D
    a pair of perpendicular planes
    Correct
12
The number of spheres of a given radius r and touching the coordinate axes is
  • A
    none of these
  • B
    8
    Correct
  • C
    6
  • D
    4
13
The equation \(\vec r = \lambda \widehat {i}represents\)
  • A
    the Y axis
  • B
    the Z axis
  • C
    the X axis
    Correct
  • D
    the YOZ plane
14
The equation \(\vec r = \lambda \widehat {i} + \mu \widehat {j} \) represents
  • A
    the Y axis
  • B
    the Z axis
  • C
    the X aixs
  • D
    the plane z = 0
    Correct
15
The equation \(\vec r = \lambda \widehat {k} \) represents
  • A
    none of these
  • B
    the Y axis
  • C
    the Z axis
    Correct
  • D
    the X axis