Find out the wrong number in the series.

Light year is a unit of

Friction can be reduced by changing from

For safety , the fuse wire used in the mains for household supply of electricity must be made of metal having

The absorption of ink by boltting paper involves

Rays from sun coverage at a point of 15 cm in front of concave mirror.Where should the object be placed so that size of its image is equal to the size of the object ?

A man presses more weight on earth at

Perimeter of a triangle with integer sides is equal to 15. How many such triangles are possible ?

Building acoustics concerns

Fly ash is a waste product from which of the following

French influence in architecture is found at

How many bricks of dimensions 20cm x 10cm x 10cm wide, if 10% of the wall is comprised of mortar ?

A truncated ( horizontally cut in mid way ) hexagonal pyramid has following numbers of surfaces, edges and vertices respectively .

The angle which an inclined plane makes with the horizontal when a body placed on it is about to slide down is know as angle of

An angle which is greater than 180 degree but less than 360 degree is known as

the equation of the plane passing through the point ( 1,-1, 2) and parallel to the plane 3x-4y-5z = 0 is

In a circle of radius 17 cm , two parallel chords are drawn opposite side of a diameter . The distance between the chord is 23cm . If the length of one chord is 16cm , then the length of the other chord is

Three vertices of  $\Delta ABC$  are A (1,4), B (-2,2) and C (3,2), then the area of  $\Delta ABC$  is 

The equation of the normal to the circle    $x^2+y^2=2x$  which is parallel to the straight line  $x+2y\ =3\$  is given by 

The tangents of two points A and B on the circle with centre O intersect at a point P.If in quadrilateral PAOB,  $\angle AOB:\angle APB\ =5:1$  , then the measure of  $\angle APB$  is given by 

The number of common tangents that can be drawn to two given circles is at the most

The distance between two parallel lines 5x-12y+2=0 and 5x -12y-3=0 is given by

If a, b, c are in A.P., as well as in G.P., then

The sum of the 24 terms of the series 

AB is straight line and O is a point on the line AB. If one draws a line OC not coinciding with OA or OB , then the $\angle AOC$  and   $\angle BOC$  are

Two girls and four boys are to be seated in a row in such  a way  that the girls do not sit together . In how many different ways can it be done ? 

Let Z denote the set of all integers, If a relation R is defined on Z as follows : (x,y)  $\in$  R if and only if x is multiple of y ,  then R is 

Geodesic domes are strong and rigid due to its __________structural elements