Tag: construction related to lines

Questions Related to construction related to lines

Construct a line segment of length $4.6\ cm$. Divide this line into $2$ equal parts and find the length of each part.

  1. $2.0\ cm$

  2. $2.1\ cm$

  3. $2.2\ cm$

  4. $2.3\ cm$


Correct Option: D
Explanation:
steps of construction :
1 . draw a line of length 4.6 cm using ruler .
2. Place the compass at one end of line segment.
3 . Adjust the compass to slightly longer than half the line segment length.
4. Draw arcs above and below the line.
 5 .Keeping the same compass width, draw arcs from other end of line.
6 . Place ruler where the arcs cross, and draw the line segment.
7. drawn line segment cuts the initial line segment  into two equal parts .
8. measure the bisected length using ruler thats comes out be $= \dfrac{1}{2} \times 4.6 = 2.3 cm$

Draw a line $AB=7.8\ cm$, what will be the $\dfrac{2}{3}$rd of $AB$.

  1. $11.7\ cm$

  2. $5.2\ cm$

  3. $3.9\ cm$

  4. $2.6\ cm$


Correct Option: B
Explanation:

Draw a line segment $AB$ of $7.8\ \ cm$ using ruler 

.$\dfrac{2}{3}AB=$ $=\dfrac { 2 }{ 3 } \times 7.8=5.2 \ cm$
Option $B$ is correct.

Construct a line $AB=6.5\ cm$. What will be the $\dfrac{1}{5}$th of $AB$ ?

  1. $4.2\ cm$

  2. $3.5\ cm$

  3. $2.4\ cm$

  4. $1.3\ cm$


Correct Option: D
Explanation:

Draw a line segment $AB$ of length $6.5\ \ cm$

$\dfrac { 1 }{ 5 } AB=\dfrac { 1 }{ 5 } \times 6.5=1.3\ \ cm$
So option $D$ is correct.

Draw a line $XY=13.6\ cm$. what will be the $\dfrac{1}{4}$th of $XY$ ?

  1. $6.8\ cm$

  2. $5.2\ cm$

  3. $3.4\ cm$

  4. $2.2\ cm$


Correct Option: C
Explanation:

Draw a line segment $XY$ of length $13.6\ \ cm$

$\dfrac { 1 }{ 4 } XY=\dfrac { 1 }{ 4 } \times 13.6=3.4\ \ cm$
Option $C$ is correct.

Draw a line $PQ=9.6\ cm$. What will be the $\dfrac{1}{3}$rd of $PQ$ ?

  1. $3.2\ cm$

  2. $4.6\ cm$

  3. $2.4\ cm$

  4. $2.5\ cm$


Correct Option: A
Explanation:

Draw a line segment $PQ$ is length $9.6\ \ cm$ using a ruler.

$\dfrac { 1 }{ 3 } PQ=\dfrac { 1 }{ 3 } \times 9.6=3.2\ \ cm$
So option $A$ is correct.

Use your compasses to draw a circle of radius as specified below. What is the diameter of each of these circles.

  1. $5\ cm$

  2. $4\ cm$

  3. $12\ cm$

  4. $7\ cm$


Correct Option: A

Steps of constructing a line segment equal to the length of given segment is written in jumbled form below:
1. Draw a line $l$. Mark a point $A$ on line $l$. Without changing compass's setting, place the compass at $A$.
2. Make an arc on the line $l$ which cuts $l$ at $B$. Now, $AB$ is a copy of $CD$.
3. Draw a line segment $CD$ of any length.
4. Fix the compass's end on $C$ and pencil on $D$. This gives the length of $CD$.

Which of the above comes first.

  1. $1$

  2. $2$

  3. $3$

  4. $4$


Correct Option: C
Explanation:

Correct sequence is :

Step 1. Draw a line segment $CD$ of any length.
Step 2 .Fix the compass's end on $C$ and a pencil on $D$. This gives length $CD.$
Step 3. Draw a line $l$. Mark a point $A$ on line $l$.Without changing compass's setting place the compass at $A$
Step 4. Make an arc on the line $l$ whcih cuts $l$ at $B$  Now $AB$ is a copy of $CD$
So the first step is $3$
Option $C$ is correct.

Choose the correct answer from the alternatives given.
Water is flowing at the rate of $5$ km/hr through a pipe of diameter $14$ cm into a rectangular tank which is $50$ m long, $44$ m wide. The time taken (in hours) for the rise in the level of water in the tank to be $7$ cm is

  1. $2$

  2. $1\dfrac{1}{2}$

  3. $3$

  4. $2\dfrac{1}{2}$


Correct Option: A
Explanation:

Water
flowed by the pipe in lh = $\pi r^2h$
= $\dfrac{22}{7} \times$ $\dfrac{7\times 7}{100\times100}$ $\times 5000 m^3 =77m^3$
Volume
of expected water in the tank = $\frac{50 \times 44 \times 7}{100} = 154
m^3$ 
Required
time= $154/77 = 2 hrs$.

In $\triangle ABC,$ if $AB=7 \ cm$ and $BC=8 \ cm$, then which of the following cannot be the length of $AC$?

  1. $17\ cm$

  2. $16\ cm$

  3. $14\ cm$

  4. $None\ of\ these$


Correct Option: D

Four distinct points $(2K , 3K), (1 , 0), (0 , 1)$ and $(0 , 0)$ lie on a circle when

  1. all values of $K$ are integral

  2. $0 < K < 1$

  3. $K < 0$

  4. For one values of $K$


Correct Option: D
Explanation:

Let A = $(0,0)$ , B$(0,1)$ , C$(2k,3k)$ , D$(1,0)$

As we can see

$AD \perp AB$

$\angle A = 90$

$\angle C = 90$

$\implies m _{BC} \times m _{DC} = -1$

$\dfrac{3k - 1}{2k} \times {3k}{2k - 1} = -1$

$\implies k(9k - 3) = -(4k - 2)k$

$k = 0 , 9k + 4k = 2+ 3 \implies 13k = 5 \implies k = \dfrac{5}{13}$

But if $k = 0$, C will be $(0,0)$ which is A

$k = \dfrac{5}{13} $ only one point.