Tag: angle and its measurement

Questions Related to angle and its measurement

Multiple choice mathematics and statistics angle and its measurement directed angles

In $\displaystyle \angle PRQ $, the two arms are:

  1. $\displaystyle \overrightarrow{PR} $ and $\displaystyle \overrightarrow{RQ} $
  2. $\displaystyle \overrightarrow{RP} $ and $\displaystyle \overrightarrow{PQ} $
  3. $\displaystyle \overrightarrow{QR} $ and $\displaystyle \overrightarrow{QP} $
  4. None of the above

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
An angle is made by the intersection of two lines and that lines are also called as arms.
In $\angle{PRO}$, the angle is formed by the intersection of $\overrightarrow{PR}$ and $\overrightarrow{RO}$ at $R$.
Hence, the two arms are $\displaystyle \overrightarrow{PR} $ and $\displaystyle \overrightarrow{RQ} $.
Multiple choice mathematics and statistics angle and its measurement directed angles

To draw an angle of $150^o$ using a pair of compass and ruler ______.

  1. Bisect angle between $120^o$ and $180^o$
  2. Bisect angle between $60^o$ and $120^o$
  3. Bisect angle between $0^o$ and $160^o$
  4. None of these

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

To draw an angle of 150° using a pair of compass and 

rule we bisect an angle between 120° and 180° 
$\rightarrow$ Since 120°<150°<180° we bisect angle
     between 120° and 180°

Multiple choice mathematics and statistics angle and its measurement directed angles

If the sum of two angles is equal to an obtuse angle, then which of the following is NOT possible?

  1. One obtuse and one acute angle

  2. One right angle and one acute angle

  3. Two acute angles

  4. Two right angles

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Obtuse angles are those angles whose measure is more than$90°$ but less than $180°$.


Since, sum of two right angles is $90°+90°=180°$.

Hence sum of two right angles can not be an obtuse angle.

Multiple choice mathematics and statistics angle and its measurement directed angles

Choose the correct answers from the alternatives given.
In $\Delta $ABC, the sides AB and AC are produced to P and Q respectively. The bisectors of $\angle PBC  \, and \,  \angle QCB $ intersect at a point 0. then $\angle BOC$ is equal to:

  1. 90- $\frac{1}{2} \angle A$
  2. 90+ $\frac{1}{2} \angle A$
  3. $120^{\circ}$ + $\frac{1}{2} \angle A$
  4. 120 - $\frac{1}{2} \angle A$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

2 $\angle 1 + \angle B = 180^{circ}$         (linear pair)
$\angle 1 = 90^{\circ}-\dfrac{1}{2}\angle B$          (1)
Similarly,
$\angle 2 = 90^{\circ} - \dfrac{1}{2} \angle C$   (2)
$\angle BOC = 180^{circ}-  (\angle 1 + \angle 2)$
=$180^{circ}- [180^{circ}-\dfrac{1}{2}$ ($\angle B + \angle C$)]
=$\dfrac{1}{2}[\angle B + \angle C] = \dfrac{1}{2} (180^{circ} - \angle A) = 90^{circ}-\dfrac{1}{2} \angle A$

Multiple choice mathematics and statistics angle and its measurement directed angles

A half turn about O is a rotation through angel of ____ or ____

  1. $-90^0, +90^0$
  2. $+180^0, -180^0$
  3. $+360^0, -360^0$
  4. $-270^0, +270^0$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A half turn is a rotation of 180 degrees. In either clockwise or counter-clockwise direction, this is represented as +180 or -180 degrees.

Multiple choice mathematics and statistics angle and its measurement degree measure of angle measure of angle radians or degrees

Convert $40^\circ \,20'$ into radian measure.

  1. $\dfrac {121}{540}\pi $ radians
  2. $\dfrac {121}{570}\pi $ radians
  3. $\dfrac {120}{513}\pi $ radians
  4. None

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Given: ${40^0}$${{{20}^{'}}}$

${40^0} + \dfrac{{{{20}^0}}}{{{{60}^0}}}  $

$=40 + \dfrac{1^o}{3} = \dfrac{{{{121}^0}}}{3}$

$radian = \dfrac{\pi }{{180^o}} \times \dfrac{{121^o}}{3}$

$\boxed{ = \dfrac{{121}}{{540}}\pi \;radians}$