Introduction to Three Dimensional Geometry - Online Test

Q1. The point equidistant from the points ( 0 , 0 , 0 ) , ( 1 , 0 , 0 ) , ( 0 , 2 , 0 ) , and ( 0 , 0 , 3 ) is
Answer : Option B
Explaination / Solution:

let the point equidistant from the points ( 0 , 0 , 0 ) , ( 1 , 0 , 0 ) , ( 0 , 2 , 0 ) , and ( 0 , 0 , 3 ) is (x ,y ,z)

then according to the given condition and  distance formula between two points we have


taking ist two expressions and solving them we get 


Similarly by taking ist and 3rd we get y = 1 and by taking ist and 4th we get z = 3/2

So the required point is ( 1/2 , 1 , 3/2 )


Q2. The plane x + y = 0 is
Answer : Option D
Explaination / Solution:
No Explaination.


Q3. The points ( 1 , 1 , 0 ) , ( 0 , 1 , 1 ) , ( 1 , 0 , 1 ) , and ( 2/3 , 2/3 , 2/3 ) are
Answer : Option B
Explaination / Solution:



Q4.  The lines 
Answer : Option A
Explaination / Solution:
No Explaination.


Q5. The lines  intersect . The shortest distance between them is
Answer : Option C
Explaination / Solution:

Since the lines intersect.Hence they have a common point in them.hence the distance will be zero

Q6. Volume of a tetrahedron is k X area of one face X length of perpendicular from the opposite vertex upon it, where k is
Answer : Option D
Explaination / Solution:

Volume of tetrahedron  where a,b,c are co-terminus edges of tetrahedron.a X b is area of one face and c is the perpendicular from the opposite vertex

Q7. A , B C and D are four points in spaces such that AB = BC = CD = DA . Then ABCD is a
Answer : Option B
Explaination / Solution:

It can be square or rhombus(all sides are equal).Angle property must be mentioned.

Q8. The foot of perpendicular from (α,β,γ) on Y axis is
Answer : Option C
Explaination / Solution:

Let P() be the point and Q (0,b,0) be any point on Y axis.

drs of PQ=(

drs of y axis (0,b,0)

Since PQ perpendicular to y axis.hence a1a2+b1b2+c1c2=0


hence the foot of perpendicular will be 


Q9. The equation  represents
Answer : Option D
Explaination / Solution:

The equation  x=0 , y=  , z= 0 which represent Y axis

Q10. The equation  represents
Answer : Option B
Explaination / Solution:

The equation   which represent generally XY plane i.e the plane y=0