# Q1. The volume of 50g of a substance is 20cm3 . If the denstiy of water is 1 g cm3, will the substance float or sink in water ? justify your answer ? Q2. Show that the energy of a vibrating pendulum is conserved ?Q3. A ball is dropped from a heigh of 10m. If the energy of the ball reduces by 40% after striking the ground, how much high can the ball bounce back ?

1.volume of substance= 20 cm3

mass of substance= 50 g

density of substance = mass/volume

=50/20

= 2.5 g/cm3

density of water = 1 g/cm3

2.5 >1

density of substance > density of water

therefore the substance will sink in water.

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dencity of water=1 g/cm3

mass=50gm

volume=20 cm3

dencity of substance=m/v

50/20=2.5 g/cm3

so it will sink.

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thnx for the formula. not the person who asked this question but it helped me.

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Atitude

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If the density of an object is more than the density of the liquid in which the object is placed the object will sink, if it is less the object will float.    density of object = Mass/ volume = 50/ 20 = 2.5 g/cm^3  The density of water is 1 g/cm^3. So, the object will sink.
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If the density of an object is more than the density of the liquid in which the object is placed the object will sink, if it is less the object will float.    density of object = Mass/ volume = 50/ 20 = 2.5 g/cm^3  The density of water is 1 g/cm^3. So, the object will sink.
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pancakes

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and maple syrup
are tasty
:-)
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it will sink
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hmm..everybody's right...
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Density = mass / volume
mass = 50g
volume = 20 cm3
Density = 50 /20 = 2.5 g/cm3
If the density of a  substance is more than the  density of water it sinks.
Here , ​density of a  substance > ​density of water
That is , 2.5 g/cm>1 ​g/cm3
Therefore , it sinks.

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volume = 20 cm3
mass = 50 g
density = mass
volume
= 50 = 2.5 g/cm3
20
density of body (2.5g/cm3) >  density of water (1 g/cm3)
therefore, the body will sink in water

hope it helps......
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Why it sink
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​​​​​​Mass = 50g
volume = 20cm³
density = mass/volume = 50/20 = 2.5 g/cm³
density of water = 1 g/cm³

Since the density of the substance is greater than the density of water, it will sink in water.

The volume of water displaced = 20 cm³
mass of water displaced = volume×density = 20×1 = 20g
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• May my anwer helps you
• THANK YOU!!!!

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