S. K. Gupta Anubhuti Gangal Class 5 Math Tenth Chapter Basics Of Geometry Exercise 39

EXERCISE 39

Point: A point is an exact location in space.

Line: A line is a straight path of points that extends on and on in both the directions without ever ending.

Line Segment: A part of a line is called a line segment.

Ray: A ray is a straight path that has one endpoint and goes on and on in one direction.

Plane: A plane is a flat surface.

Angles: An angle is a figure formed by two rays meeting at a common endpoint.

Interior Angle: The inside of an angle that is the region between the rays is called the interior of the angle.

Exterior Angle: The points of the plane that do not lie on the arms or in the interior of the angle are in the exterior of the angle.

Degree: The standard unit of measure for angles is the degree.

Protractor: The instrument for measuring angles is called a protractor.

(1) Which of the following has a fixed length?

(a) A line

(b) A ray

(d) A point

Ans: (c) A line segment

(2) Classify as rays, lines and line segments. Also, name them.

(3) State True (T) or False (F).

(a) A ray has a define length. = False

(b) A line cannot be drawn on a piece of paper = True

(d) A line segment has no endpoints = False

(e) A plane has fixed boundary = False

(4) Count and name the line segments in each of the following figures.

Ans: (a) 8; AB, BC, CD, DE, EF, FG, GH, HA

(b) 12; AB, BC, CD, DE, EF, FG, GH, HI, IJ, JK, KL, LA

(5) Name the rays, and line segments in the following figures.