1. Which instrument is used to draw a circle?
Answer:
Explanation:
A compass is used to draw circles and arcs.
2. What is the main purpose of a protractor?
Answer:
Explanation:
A protractor is used to measure and construct angles.
3. Which of the following is essential to construct a unique triangle when three sides are given?
Answer:
Explanation:
With the help of a ruler and compass, a unique triangle can be constructed using its three given sides (SSS criterion).
4. To construct a 60° angle, which basic construction is required?
Answer:
Explanation:
The angles of an equilateral triangle are 60°. Hence, constructing one helps in getting the desired angle.
5. Which instrument is NOT typically used for constructions in practical geometry?
Answer:
Explanation:
While erasers are handy for corrections, they aren't primarily used for geometrical constructions.
6. To bisect a given angle, which instruments are necessary?
Answer:
Explanation:
An angle can be bisected using a compass and ruler.
7. What is the main purpose of a set-square?
Answer:
Explanation:
Set-squares are usually used to draw perpendicular and parallel lines.
8. To construct a 90° angle, we can use:
Answer:
Explanation:
A 90° angle can be constructed using a compass and ruler, or directly with a set-square.
9. The angle bisector of a given angle divides it into:
Answer:
Explanation:
An angle bisector divides the given angle into two equal parts.
10. A rhombus with a side of 5 cm can be constructed using:
Answer:
Explanation:
A rhombus has all sides equal. Therefore, by the SSS criterion, it can be constructed using the given side length.
11. Which is NOT a basic construction in practical geometry?
Answer:
Explanation:
Drawing an ellipse requires a specific set of tools and isn't considered a basic construction in practical geometry.
12. The construction of a triangle with two given sides and the included angle is based on which criterion?
Answer:
Explanation:
The SAS criterion involves two sides and the included angle.
13. To divide a line segment into a number of equal parts, you would need:
Answer:
Explanation:
A line segment can be divided into equal parts using a ruler and compass.
14. To construct a parallelogram, which of the following sets of measurements is NOT sufficient?
Answer:
Explanation:
Two adjacent angles and a side aren't sufficient to construct a unique parallelogram.
15. A line segment is drawn using:
Answer:
Explanation:
Line segments are drawn using a ruler.
16. A triangle is said to be constructed uniquely if:
Answer:
Explanation:
A unique triangle can be constructed if any three of its elements (like SSS, SAS, ASA, or AAS) are given.
17. Which of the following can be constructed using only a straightedge?
Answer:
Explanation:
A perpendicular bisector can be constructed using only a straightedge if the points where the circle intersects the line segment are marked.
18. A right-angled triangle can be constructed uniquely when:
Answer:
Explanation:
If one angle (which is 90°) and the hypotenuse are given, a right-angled triangle can be constructed uniquely.
19. If a triangle is constructed with two angles and the included side, it follows the:
Answer:
Explanation:
Two angles and the included side relate to the ASA criterion.
20. To draw a line parallel to a given line through a point, which instrument is crucial?
Answer:
Explanation:
A set-square helps in drawing a line parallel to a given line through a specific point.