Question

♥️Hello Friends♥️

Q. 1 . Why Does this happen ?

a.) A Ship dips to a larger depth in fresh water as compared to marine water .

b.) Fruits can easily be cut with a sharp knife .

c). The wall of a dam is broad at it's base.

d). If a stationary bus suddenly speeds up, Passengers are thrown in the backward direction.

__________________________________________

Q3. , Q.4 , Q.5 Are in the attachment
__________________________________________


♥️Stay Safe Friends♥️​

Answer 1

QUESTION:

❶ (a) The density of marine water is more than the density of freshwater because of the presence of salts that's why a Ship dips to a larger depth in fresh water as compared to marine water.

(b) The edge of cutting tools like knife is made sharp to decrease the effective surface area. It results in increasing the effect of pressure. if the edge is blunt means a larger area, that results effect of pressure decreased.

(c) The pressure exerted by the water increases with increase in depth. The dam contains large amount of water and as we go in depth the pressure exerted by large amount of water increases to very high.

(d) The lower part of his body, in contact with seat, starts moving along with the bus, but the upper part of his body tends to remain at rest, because of inertia of rest.

QUESTION:

❸ The density of a metal is $\bf{ 10.8 \times 10^3 kg/m^3}$. Find the relative density of the metal.

GIVEN:

• Density of metal = 10.8 $\times$ 10³ kg/m³

TO FIND:

• What is the relative density of the metal ?

SOLUTION:

To find the relative density of the metal, we use the formula:-

$\bf{ Relative \: density = \dfrac{Density \: of \: metal}{Density \: of \: water}}$

【 As we know that the density of water is 1000 kg/m³】

According to question:-

$\rm{\rightharpoonup Relative \: density = \dfrac{ 10.8 \times \cancel{10^3}}{\cancel{1000}}}$

$\large\bf{\star \: Relative \: Density = 10.8 \: \star }$

➠ Relative density is the ratio of two similar quantities, so it has no unit.

____________________

QUESTION:

❹  Volume of an object is 20cm³ and the mass is 50 g. Density of water is 1 g/cm³. Will the object float or sink in water?

GIVEN:

• Volume of object = 20 cm³
• Mass of object = 50 g
• Density of water = 1 g/cm³

TO FIND:

• Will the object float or sink in water ?

SOLUTION:

We know that the formula for finding the Density of object is:-

$\bf{\star \: Density = \dfrac{mass}{Volume}\: \star}$

According to question:-

$\rm{\rightharpoonup Density = \cancel \dfrac{50}{20}}$

$\bf{\star \: Density = 2.5 \: g/cm^3 \: \star }$

【If the density of a substance is more than the density of fluid, it will sink in the fluid】

❝ The object will sink in water. ❞

____________________

QUESTION:

❺ The volume of a plastic covered sealed box is 350 cm³ and mass is 500 g. Will the box float on water or sink in water ? What will be the mass of water displaced by box ?

GIVEN:

• volume of a plastic covered sealed box = 350 cm³
• Mass of box = 500 g

TO FIND:

• Will the box float on water or sink in water ?
• What will be the mass of water displaced by box ?

Firstly, we have to find the Density of the box

To find the Density of the box, we use the formula:-

$\bf{\star \:Density = \dfrac{mass}{Volume}\: \star}$

According to question:-

$\rm{\rightharpoonup Density = \cancel\dfrac{500}{350}}$

$\bf{\star \:Density = 1. 42 g/cm^3 (approx) \: \star }$

➤ The density of box is more than the density of water that's why the box will sink in water.

✬ Mass of water displaced by box = Volume of box $\times$ Density of water

$\rm{\rightharpoonup Mass = 350 \times 1 }$

$\bf{ \star \: Mass = 350 g \: \star}$

❝ Hence, the mass of water displayed by box is 350 g ❞

____________________

Answer 2

Answer -

Answers are in the attachment

Note -

Sorry but I have not attached the answers of Question in the attachment.

HoPe iT HeLpS YoU ♥️♥️♥️