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2 years ago

Explain why pumice floats and why ironwood sinks

Physics

2 answers:

almond37 [142]2 years ago

6 0

Answer:

A quick way of describing density is to describe an object as heavy or light for its size. Pumice stone, unlike regular rock, does not sink in water because it has a low density. An ironwood branch is very dense and sinks in water.

Hope that helps. x

zhuklara [117]2 years ago

4 0

Answer:

Pumice is trapped in gas when the temperature is warm, but as the temp drops, it becomes dense, due to air bubbles. Iron wood is denser than water, thus making it sink.

Explanation:

You might be interested in

Calculate the density of a solid cube that

tia_tia [17]

Ok so if each side is 4.53 cm, we can multiply 4.53 x 4.53 x 4.53 to get the volume (since v= l x w x h). Density equals mass/volume, so

519 g/4.53 cm
114.57 g/cm^3 (since none of the units cancel)

4 0

3 years ago

A block, M1=10kg, slides down a smooth, curved incline of height 5m. It collides elastically with another block, M2=5kg, which i

erma4kov [3.2K]

Answer:

2.86 m

Explanation:

Given:

M₁ = 10 kg

M₂ = 5 kg

$\mu_k$ = 0.5

height, h = 5 m

distance traveled, s = 2 m

spring constant, k = 250 N/m

now,

the initial velocity of the first block as it approaches the second block

u₁ = √(2 × g × h)

u₁ = √(2 × 9.8 × 5)

u₁ = 9.89 m/s

let the velocity of second ball be v₂

now from the conservation of momentum, we have

M₁ × u₁ = M₂ × v₂

on substituting the values, we get

10 × 9.89 = 5 × v₂

v₂ = 19.79 m/s

now,

let the velocity of mass 2 when it reaches the spring be v₃

from the work energy theorem, we have

Work done by the friction force = change in kinetic energy of the mass 2

$0.5\times5\times9.8\times2 = \frac{1}{2}\times5\times( v_3^2-19.79^2)$

v₃ = 20.27 m/s

now, let the spring is compressed by the distance 'x'

therefore, from the conservation of energy

we have

Energy of the spring = Kinetic energy of the mass 2

$\frac{1}{2}kx^2=\frac{1}{2}mv_3^2$

on substituting the values, we get

$\frac{1}{2}\times250\times x^2=\frac{1}{2}\times5\times20.27^2$

x = 2.86 m

8 0

3 years ago

When did humans learn that the earth is not the center of the universe?

Vinvika [58]

Answer:

When did humans learn that the Earth is not the center of the universe?

Answer

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4 Answers

Asked in 3 Spaces

Science - Next Generation

Alexander Somm

, Consultant, Investor Relations at Novelpharm AG (2015-present)

Answered Oct 16

What, it isn’t?!

Sorry, I had to.

As far as I have read and understood, the Sumerians and later the Babylonians both had astronomical calendars that already differentiated planets and stars. Earth was not the center to them, the Sun likely was. That was around 2,200 - 1,600 BC.

After that, Greek philosopher Aristarchus of Samos (310 - 230 BC) was the first (recorded) to have believed the solar system was organized around the Sun, rather than the Earth. His heliocentric model was unpopular during Aristarchus’ lifetime, although it would inspire astronomers centuries later, such as Copernicus and Galileo.

Now, there are numerous archeological findings (cave paintings) and studies, that all suggest an understanding of complex astronomy in prehistoric times dating back as far as 40,000 years. This also explains how early, prehistoric migrants may have navigated the seas.

Explanation:

hope it helps

have a good day

4 0

2 years ago

An apple falls from a tree and hits the ground 9.98 m below. with what speed will it hit the ground

cupoosta [38]

The answer to this question is 13,537

8 0

3 years ago

By what factors does the speed of the elctron exceed that of the proton?

____ [38]

Answer:

» An electron is lighter than a proton.

explanation:

${ = \: \sf{an \: electron \: has \: formula \: \: }}{ \bf{ {}^{0}_{ - 1}e }}$

hence it's mass number is zero

${ = \: \sf{an \: electron \: is \: helium \: particle \: \: }}{ \bf{ {}^{4} _{2}He }}$

hence it's mass number is 4

Therefore, proton is heavier than electron

» An electron has a small charge magnitude than a proton.

Explanation:

An electron has charge of -1 while proton has charge of +2, therefore electron is less deflected by any energetic fields than a proton

8 0

3 years ago