Ask question

Ask question

All categories

3 years ago

6

Mary is investigating the densities of objects. She is going to use the table below to record her results. Which of these can sh

e find using a ruler?

1 answer:

Dennis_Churaev [7]3 years ago

8 0

<u><em /></u>

<u><em>answer</em></u>

block of aluminium

You might be interested in

Explain in detail what information can be learn about atoms of different elements by examining the periodic table . For the Maxi

raketka [301]

Answer:

We know the information about atomic size, energy, electronic configuration etc. of atom from the periodic table.

Explanation:

Periodic table is the arrangement of elements that are arranged according to their properties and electronic configuration.
In periodic table, on furthest right side of the periodic table, noble gases like He, Ne, Ar etc are arranged.
The atomic number of element increases while moving from left towards right in the periodic table.
The metallic character of element decreases as we proceed the table towards right.
They readily accept electron to fill the valence shell hence becoming more metallic in character.

5 0

3 years ago

When a condenser discharges electricity, the instantaneous rate of change of the voltage is proportional to the voltage in the c

e-lub [12.9K]

Answer:

460.52 s

Explanation:

Since the instantaneous rate of change of the voltage is proportional to the voltage in the condenser, we have that

dV/dt ∝ V

dV/dt = kV

separating the variables, we have

dV/V = kdt

integrating both sides, we have

∫dV/V = ∫kdt

㏑(V/V₀) = kt

V/V₀ = $e^{kt}$

Since the instantaneous rate of change of the voltage is -0.01 of the voltage dV/dt = -0.01V

Since dV/dt = kV

-0.01V = kV

k = -0.01

So, V/V₀ = $e^{-0.01t}$

V = V₀ $e^{-0.01t}$

Given that the voltage decreases by 90 %, we have that the remaining voltage (100 % - 90%)V₀ = 10%V₀ = 0.1V₀

So, V = 0.1V₀

Thus

V = V₀ $e^{-0.01t}$

0.1V₀ = V₀ $e^{-0.01t}$

0.1V₀/V₀ = $e^{-0.01t}$

0.1 = $e^{-0.01t}$

to find the time, t it takes the voltage to decrease by 90%, we taking natural logarithm of both sides, we have

㏑(0.01) = -0.01t

So, t = ㏑(0.01)/-0.01

t = -4.6052/-0.01

t = 460.52 s

3 0

3 years ago

If the radius of the sun is 7.001×105 km, what is the average density of the sun in units of grams per cubic centimeter? The vol

xenn [34]

Answer:

Average density of Sun is 1.3927 $\frac{g}{cm}$ .

Given:

Radius of Sun = 7.001 × $10^{5}$ km = 7.001 × $10^{10}$ cm

Mass of Sun = 2 × $10^{30}$ kg = 2 × $10^{33}$ g

To find:

Average density of Sun = ?

Formula used:

Density of Sun = $\frac{Mass of Sun}{Volume of Sun}$

Solution:

Density of Sun is given by,

Density of Sun = $\frac{Mass of Sun}{Volume of Sun}$

Volume of Sun = $\frac{4}{3} \pi r^{3}$

Volume of Sun = $\frac{4}{3} \times 3.14 \times [7.001 \times 10^{10}]^{3}$

Volume of Sun = 1.436 × $10^{33}$ $cm^{3}$

Density of Sun = $\frac{ 2\times 10^{33} }{1.436 \times 10^{33} }$

Density of Sun = 1.3927 $\frac{g}{cm}$

Thus, Average density of Sun is 1.3927 $\frac{g}{cm}$ .

4 0

3 years ago

Am I right? Please help!

JulsSmile [24]

I believe you are right.

3 0

3 years ago

Longitudinal waves cannot travel through a vacuum. True False

JulsSmile [24]

FALSE <span>Only electromagnetic </span>waves<span> can </span>travel through a vacuum<span>; mechanical </span>waves<span> such as sound </span>waves<span> require a particle-interaction to transport their energy. There are no particles in a </span>vacuum<span>. </span>Waves<span> are either </span>longitudinal<span> or transverse.
</span>Hoped i helped :):)

4 0

3 years ago