Tag: conversion between different units

Questions Related to conversion between different units

A copper sphere of diameter 6 cm is drawn into a wire of diameter 0.4 cm. The length of the wire is

  1. 6 m

  2. 8 m

  3. 9 m

  4. None of these


Correct Option: C
Explanation:

Volume of wire (cyl)= Vol of sphere 
$\displaystyle \Rightarrow \pi \times \left ( 0.2 \right )^{2}\times h=\dfrac{4}{3}\times \pi \times 3^{3}$
$\displaystyle\Rightarrow h=900 cm = 9 m $

Diameter of a copper sphere is 6 cm. The sphere is melted and drawn into a wire of uniform circular cross section which is 72 cm long .The diameter of the wire is nearly

  1. 2.8 cm

  2. 2.7 cm

  3. 1.4 cm

  4. None of these


Correct Option: C
Explanation:

Volume of wire (cyl)=Volume of sphere 
$\displaystyle \Rightarrow \pi r^{2}\times 72=\dfrac{4}{3}\pi \times 3^{3}$
$\displaystyle \Rightarrow r=\dfrac{1}{\sqrt{2}}cm$
Thus diameter$\displaystyle \dfrac{2}{\sqrt{2}}cm=\sqrt{2}cm=1.4cm$

A right circular cylinder and a sphere are of equal volumes and their radii are also equal If h is the height of the cylinder and d is the diameter of the sphere then

  1. $\displaystyle \frac{h}{3}=\frac{d}{2} $

  2. $\displaystyle \frac{h}{2}=\frac{d}{3} $

  3. $2h = d$

  4. $h = d$


Correct Option: B
Explanation:

Volume of cylinder = Volume of sphere
$\displaystyle \Rightarrow \pi \left ( \dfrac{d}{2} \right )^{2}h=\dfrac{4}{3}\pi \left ( \dfrac{d}{2} \right )^{3}$
$\displaystyle \Rightarrow h=\dfrac{2}{3}d\Rightarrow \dfrac{h}{2}=\dfrac{d}{3}$

There is a rod of length $4\ cm$ and another rod of length $500\ mm$ has been joined to the first rod. Then the length of the rod(in cm) formed by joining these $2$ is :

  1. $450\ cm$

  2. $54\ cm$

  3. $9\ cm$

  4. $4.5\ cm$


Correct Option: B
Explanation:
Length of first Rod is $4cm$

Length of second Rod is $500mm$

Total Length of the Rod  by joining these two rods is $4cm$ $500mm$

We know that, $1$  $centimeter =10$ $mm$, $1$  $mm =\dfrac{1}{10}$  $cm$

We need to convert  $4$ $cm$ $500$  $mm$  to  $centimeter$
$4cm$ $500$  $mm$ $ = 4cm + 500mm$
Now, $500$ $mm =\dfrac{1}{10} \times 500$ $cm$ $= 50$  $cm$
$\therefore 4cm\ 500\ mm=4cm + 500mm=(4+50)cm$ $=54\ cm$

So, Option $B$ is correct

1 MB = _________KB

  1. $\displaystyle 2^{8}$

  2. $\displaystyle 2^{20}$

  3. $\displaystyle 2^{9}$

  4. $\displaystyle 2^{10}$


Correct Option: D
Explanation:

$ 1 MB = 1024 KB $  which is also equal to $ {2}^{10} KB $

Express $49$ milligrams in centigrams.

  1. $490$ centigrams

  2. $4900$ centigrams

  3. $0.049$ centigrams

  4. $4.9$ centigrams


Correct Option: D
Explanation:

$1$ centigram is equal to $10$ milligrams.
Therefore, $49$ milligrams is equal to $\dfrac{1}{10} \times 49 = 4.9$ centigrams.

Convert the following into quintal:
$400\ $ ton

  1. $400$ quintal

  2. $4,000$ quintal

  3. $40$ quintal

  4. $4$ quintal


Correct Option: B
Explanation:

We know that


$1$  $ton =10$  $quintal$

$1$  $quintal =\dfrac1{10}$  $ton$

Given That, we have to convert $400$  $ton$  to   $quintals$

$400$  $tons =400 \times 10$  $quintals$

                   
                   $=4,000$  $quintals$

So, option $B$ is correct

Convert the following into kilograms :
$2.3$ ton

  1. $23\ kg$

  2. $23,000\ kg$

  3. $230\ kg$

  4. $2,300\ kg$


Correct Option: D
Explanation:

We know that


$1$  $ton =1000$  $kilograms$

$1$  $kg =\dfrac1{1000}$  $ton$

Given That, we have to convert $2.3$  $tons$  to   $kg$

$2.3$  $ton =2.3 \times 1000$  $kg$

                    $ = 2,300$  $kg$

So, option $D$ is correct

Convert the following into kilograms :
$400\ gm$ 

  1. $0.4\ kg$

  2. $4\ kg$

  3. $40\ kg$

  4. $400\ kg$


Correct Option: A
Explanation:

We know that


$1$  $kilogram =1000$  $gram$

$1$  $gm =\dfrac1{1000}$  $kg$

Given That, we have to convert $400$  $gm$  to   $kg$

$400$  $gm =\dfrac{1}{1000} \times 400$  $kg$

                    $ =\dfrac{400}{1000} $  $kg$

                   $=0.4$  $kg$

So, option $A$ is correct

Convert the following into tons :
$670$ quintal

  1. $6700$ tons

  2. $670$ tons

  3. $67$ tons

  4. $6.7$ tons


Correct Option: C
Explanation:

We know that


$1$  $ton =10$  $quintal$

$1$  $quintal =\dfrac1{10}$  $ton$

Given That, we have to convert $670$  $quintal$  to   $tons$

$670$  $quintals =\dfrac{1}{10} \times 670$  $tons$

                    $ =\dfrac{670}{10} $  $tons$

                   $=67$  $tons$

So, option $C$ is correct