The radius of a wire is decreased to one –third if volume remains the same length will increase

Related Mcqs:

1. A metallic sphere of radius 12 cm is melted and drawn into a wire, whose radius of cross section is 16 cm. What is the length of the wire?

   A. 45 cm
   B. 18 cm
   C. 90 cm
   D. None of these

2. The length of a rectangle is twice its breadth, if length is decreased by 5 cm and the breadth is increased by 5 cm. The length of the rectangle is_________?

   A. 20 cm
   B. 30 cm
   C. 40 cm
   D. 50 cm

3. The length of the wire of 0.2mm radius that can be drawn after melting a solid copper sphere of diameter 18cm?

   A. 24.3 m
   B. 243 m
   C. 2430 m
   D. 24300 m

4. A wire in the form of a circle of radius 3.5 m is bent in the form of a rectangule, whose length and breadth are in the ratio of 6 : 5. What is the area of the rectangle?

   A. 60 cm2
   B. 30 cm2
   C. 45 cm2
   D. 15 cm2

5. The length of a rectangle is two – fifths of the radius of a circle. The radius of the circle is equal to the side of the square, whose area is 1225 sq.units. What is the area (in sq.units) of the rectangle if the rectangle if the breadth is 10 units?

   A. 140
   B. 156
   C. 175
   D. 214

6. A and B are two fixed points 5 cm apart and c is a point on AB such that AC = 3 cm. If the length of AC is increased by 6 % the length of CB is decreased by:_________?

   A. 6 %
   B. 7 %
   C. 8 %
   D. 9 %

7. When the numerator of a fraction is decreased by 25% and its denominator is decreased by 20%, the new fraction obtained is 3/4. Find the original fraction?

   A. 5/4
   B. 4/7
   C. 5/6
   D. 6/7
   E. None of these

8. In a Circle of Radius 5 cm if AB and AC are two equal chords of length 6cm each, then the length of chord BC is___________?

   A. 24/5 cm
   B. 12/5 cm
   C. 7/5 cm
   D. None of these

9. If the price of petral is increased by 20% by what percentage should the consumption be decreased by the consumer if the expenditure on petrel remains unchanged?

   A. 16 2/3%
   B. 6 2/3%
   C. 8%
   D. 15%

10. The wire bent in the form of a square enclose an area of 484 Sq.cm. If the same wire is bent so as to from a circle than the area enclosed will be_________?

    A. 484Sq.cm
    B. 538 2/7 Sq.cm
    C. 616 Sq.cm
    D. 644 Sq.cm