Question

please let me know their answers?
It is Physics

solve my problem I'll mark you as brainliest​

Answer 1

Formulae to be used:

$\pink{\boxed{\bf{Density=\frac{Mass}{Volume}}}}$

$\purple{\boxed{\bf{Volume=\frac{Mass}{Density}}}}$

$\blue{\boxed{\bf{Mass=Density\times Volume}}}$

$\rule{190}{1}$

2)

Given:

Dimensions of hall(air)= 10m×7m×5m

Density of air= 1.11 kg m⁻³

Solution:

On using formula, we get

$\longrightarrow\rm{Mass\:of\:air=Density\:of\:air\times Volume\:of\:air}$

$\longrightarrow\rm{Mass\:of\:air=1.11\times10\times7\times5}$

$\longrightarrow\rm{Mass\:of\:air=388.5\:Kg}$

$\rule{190}{1}$

3)

Given:

Density of aluminium= 2.7 g cm⁻³

Solution:

$\longrightarrow\rm{Density=2.7\:g\:cm^{-3}=2.7\times1000=2700\:kg\:m^{-3}}$

Note: To change g cm⁻³ into kg m⁻³, multiply the density by 1000

$\rule{190}{1}$

4)

Given:

Density of alcohol= 600 kg m⁻³

Solution:

$\longrightarrow\rm{Density=600\:g\:cm^{-3}=\dfrac{600}{1000} =0.6\:g\:cm^{-3}}$

Note: To change kg m⁻³ into g cm⁻³, divide the density by 1000

$\rule{190}{1}$

5)

Given:

Mass of zinc piece= 438.6 g

Volume of zinc piece= 86 cm³

Solution:

On using formula, we get

$\longrightarrow\rm{Density\:of\:piece=\dfrac{Mass\:of\:piece}{Volume\:of\:piece}}$

$\longrightarrow\rm{Density\:of\:piece=\dfrac{438.6}{86}=5.1\:g\:cm^{-3}}$

$\rule{190}{1}$

6)

Given:

Mass of wood piece= 150 g

Volume of wood piece= 200 cm³

Solution:

We know that,

• g cm³ is C.G.S. unit of density
• kg m³ is S.I. unit of density

On using formula, we get

$\longrightarrow\rm{Density\:of\:piece=\dfrac{Mass\:of\:piece}{Volume\:of\:piece}}$

(a)

$\longrightarrow\rm{Density\:of\:piece=\dfrac{150}{200}=0.75\:g\:cm^{-3}}$

(b)

$\rm{Density=0.75\:g\:cm^{-3}=0.75\times1000=750\:kg\:m^{-3}}$

$\rule{190}{1}$

7)

Given:

Mass of wood= 6000 kg

Density of wood= 0.8 g cm³= 800 kg m³

Solution:

On using formula, we get

$\longrightarrow\rm{Volume\:of\:wood=\dfrac{Mass\:of\:wood}{Density\:of\:wood}}$

$\longrightarrow\rm{Volume\:of\:wood=\dfrac{6000}{800}=7.5\:m^{3}}$

$\rule{190}{1}$

8th question is incomplete