Self Studies

Surface Areas and Volumes Test - 43

Result Self Studies

Surface Areas and Volumes Test - 43
  • Score

    -

    out of -
  • Rank

    -

    out of -
TIME Taken - -
Self Studies

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Self Studies Self Studies
Weekly Quiz Competition
  • Question 1
    1 / -0
    The addition of curved surface and circular surfaces are called

    Solution
    The total surface area includes curved surface area and two circular surfaces.
  • Question 2
    1 / -0
    Find the surface area of a cube in square inches, whose each edge measures $$3$$ inches.
    Solution
    Surface area of cube$$=6a^2$$
    Where '$$a$$' is the edge of the cube
    Surface area $$=$$ $$6\times (3)^2$$
    $$\Rightarrow 6\times 9=54$$ square inches
  • Question 3
    1 / -0
    What is the surface area of a cylinder that has a top and bottom if the height is $$8.5$$ units and the diameter is $$3$$ units?
    Solution
    Given: height $$= 8.5$$, diameter $$= 3$$
    $$\therefore$$ radius $$=$$ $$\dfrac{D}{2}=\dfrac{3}{2}=1.5$$
    Surface area $$=$$ $$2\pi rh +2\pi r^2$$
    $$=2\pi\times1.5\times 8.5+2\pi\times 1.5^2$$
    $$=2\pi(12.75+2.25)$$
    $$=2\pi(15)$$
    $$=30\pi$$ sq.units
  • Question 4
    1 / -0
    How much more water is needed to fill the tank to its brim?

    Solution
    Capacity of the tank $$=$$ Volume of tank

                                       $$= 20\times 20\times 15 = 6000\ cm^3$$

    Volume of water filled in the tank  $$= 20\times 8\times 15$$

                                                             $$ =  2400\ cm^3$$

    Volume yet to be filled in tank to its brim $$= 6000\ cm^3 - 2400\ cm^3$$

                                                                         $$ = 3600 \ cm^3$$
  • Question 5
    1 / -0
    If the circumference of the inner edge of a hemispherical bowl is $$\dfrac {132}{7} cm$$, then what is its capacity?
    Solution
    $$2\pi r = \dfrac {132}{7}\Rightarrow r = \dfrac {132}{7}\times \dfrac {1}{2\times \dfrac {22}{7}}$$
    $$r = 3$$
    $$Capacity = \dfrac {2}{3}.\pi r^{3} = \dfrac {2}{3}.\pi 3^{3} = 18\pi$$
  • Question 6
    1 / -0
    A closed metallic cylindrical box is 1.25 m high and its base radius is 35 cm. If the sheet metal costs Rs. 80 per m$$^2$$, the cost of the material used in the box is
    Solution
    T.S.A. of cyl $$ = 2\pi rh+2\pi r^{2} = 2\pi \times \left ( \dfrac{35}{100} \right )\times 1.25+2\pi \left ( \dfrac{35}{100} \right )^{2} $$
    $$ \Rightarrow TSA = 3.52\,m^{2} $$ & as cost of $$ 1\,m^{2} $$ is Rs 80 
    $$ \Rightarrow $$ Total cost $$ = 3.52\times 80 = Rs\,281.6 $$ 
  • Question 7
    1 / -0
    Find the total surface area of a hemisphere of radius $$10$$ cm.
    Solution
    T.S.A of hemisphere is $$ (2\pi r^{2}+\pi r^{2}) $$
    $$ \Rightarrow T.S.A = 3\pi r^{2} = 3\pi (10)^{2} = \boxed{942.86} $$ 
  • Question 8
    1 / -0
    The curved surface area of a right circular cone of radius $$11.3$$ cm is $$355$$ cm$$^2$$. What is its slant height?
    Solution
    Given, radius $$r=11.3 \text{ cm}$$

    and curved surface area $$=355 \text{ cm}^2$$.

    We know, curved surface area of a cone $$ =\pi rl $$

    $$11.3 \pi  l= 355$$

    $$l = \dfrac{355}{\pi \times 11.3}$$

    $$ {l = 10\text{ cm}} $$ 

    Therefore, option $$C$$ is correct.
  • Question 9
    1 / -0
    Each edge in a cube is $$5\ cm$$. What is the surface area in square cm?
    Solution
    Surface area of a cube is $$6a^2$$ where $$a$$ is an edge of the cube.

    The surface area of the cube with edge $$5$$cm is given by:

    $$A=6a^{ 2 }=6\times (5)^{ 2 }=6\times 25=150cm^{ 2 }$$
  • Question 10
    1 / -0
    The diameter of the moon is approximately one fourth of the diameter of the earth. Find the ratio of their surface areas.
    Solution
    Let the diameter of earth be $$D$$ & of moon be $$d$$.

    $$\therefore $$ According to the statement, $$ d=\dfrac { D }{ 4 } $$.

    Then, $$ \dfrac{d}{2}=\dfrac { D }{ 2\times4 } $$.

    $$\Rightarrow r=\dfrac { R }{ 4 }$$

    $$ \Rightarrow \dfrac { r }{ R } =\dfrac { 1 }{ 4 } $$.

    $$\therefore $$ The ratio of their surface areas is $$= \dfrac { 4\pi { r }^{ 2 } }{ 4\pi { R }^{ 2 } } ={ \left( \dfrac { r }{ R }  \right)  }^{ 2 }={ \left( \dfrac { 1 }{ 4 }  \right)  }^{ 2 }=\dfrac { 1 }{ 16 } =1:16$$.

    Hence, option $$B$$ is correct.
Self Studies
User
Question Analysis
  • Correct -

  • Wrong -

  • Skipped -

My Perfomance
  • Score

    -

    out of -
  • Rank

    -

    out of -
Re-Attempt Weekly Quiz Competition
Self Studies Get latest Exam Updates
& Study Material Alerts!
No, Thanks
Self Studies
Click on Allow to receive notifications
Allow Notification
Self Studies
Self Studies Self Studies
To enable notifications follow this 2 steps:
  • First Click on Secure Icon Self Studies
  • Second click on the toggle icon
Allow Notification
Get latest Exam Updates & FREE Study Material Alerts!
Self Studies ×
Open Now