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3 years ago

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1. Martha bought a six pack of soda on Thursday. She promised her neighbor, Mr. Jimmy, that she would save the cans for him. Wha

t are they doing to help our ecosystem?

1 answer:

PIT_PIT [208]3 years ago

8 0

Answer:

They are helping the ecosystem

Explanation:

They are helping the ecosystem by making sure those cans are going to be either

a) recycled properly

b) up-cycled for a project of some sorts

You might be interested in

All recorded measurements require a number followed by a _______ .

Dmitry [639]

Answer: unit

Jusitification:

An plain number does not inform the real meaning of the measure if you do not inform the unit of measurement.

Without the unit you cannot tell the real magnitude of objects or phenomena measured.

For example, suppose that some one asks how long is a boat and the answer is 20. What is it? 20 meters? 20 feet? 20 yards? You do not really know if it is a big boat or a small one until you inform the unit of measurement.

The same is true with any measurement. If you measure volumen you have to tell is the number reported is galon, liters, cubic centimeter, mililiter, cubir meter, or what.

7 0

3 years ago

Hockey puck B rests on a smooth ice surface and is struck by a second puck A, which has the same mass. Puck A is initially trave

Marina86 [1]

Answer:

$a.v_{b2}=6.8544 \ m/s\\\\b. v_{a2}=12.891 \ m/s\\\\c. \theta _b=62\textdegree$

Explanation:

Puck A's initial speed is $v_a_1=14.6m/s$ and move in a direction $\theta_b=28.0\textdegree$ after the collision.

# $P_1=P_2$ since there's no external force on the system( $P=mv).$

#The collision equation can be written as;

$m_av_a_1+m_bv_b_1=m_av_a_2+m_bv_b_2$

The kinetic energies before and after the collision are expressed as:

$K_a_1+K_{b1}=K_a_2+K_{b2}, \ K=0.5mv^2$

$0.5m_av_a_1+0.5m_b(0)=0.5m_av_a_2+0.5m_bv_b_2\\\\14.6^2=v_{a2}^2+v_{b2}^2\\\\v_{b2}^2=213.16-v_{a2}^2$

Let +x along A's initial direction and +y along A's final direction makes the angle $62\textdegree$

$\dot v_{a1}=14.6i\\\\\dot v_{a2}=(v_{a2} \ cos \ 28\textdegree)i+(v_a_2\ sin \ 28\textdegree)j\\\\\dot v_{b2}=v_{b2x}i+v_{b2y}j$

#Substitute in $v_{b2}^2=213.16-v_{a2}^2$ :

$\dot v_{b2}=(14.6i)-\dot v{a2}\\\\\dot v_{b2}.\dot v_{b2}=v_{b2}^2\\\\\#Right \ side\\\\(14.6i-\dot v{a2}).(14.6i-\dot v{a2})=(14.6i)^2+\dot v_{a2}^2.\dot v_{a2}^2-2(14.6i).\dot v_{a2}\\\\=213.16+v_{a2}^2-2(14.6i).(v_{a2}\ cos 28\ \textdegree i+v_{a2} \ sin \ 28\textdegree j)\\\\v_{b2}^2=213.16+v_{a2}^2-29.2\ cos \ 28\textdegree v_{a2}\ \ v_{b2}^2=213.16-v_{a2}^2\\\\213.16-v_{a2}^2=213.16+v_{a2}^2-29.2\ cos \ 28\textdegree v_{a2}\\\\2v_a2}^2=29.2\ cos\ 28 \textdegree v_{a2}\\\\$

$v_{a2}=12.891\ m/s$

Hence, the the speed of puck A after the collision is 12.891 m/s

#. The velocity of A after the collision is;

$\dot v_{a2}=12.891 \ cos \ 28 \textdegree i+12.891 \ sin \ 28\textdegree j\\\\=11.382i+6.052j$

Substitute $\dot v_{a2}$ into $\dot v_{b2}=(14.6i)-\dot v{a2}$ :

$\dot v_{b2}=14.6i-(11.382i+6.052j)\\\\=3.218i-6.052j$

This is the velocity of puck B after the collision, it's speed is:

$v_{b2}=\sqrt{v_{b2x}^2+v_{b2y}^2}\\\\=\sqrt{3.218^2+(-6.052)^2}\\\\v_{b2}=6.8544 \ m/s$

The velocity of puck B after the collision is 6.8544 m/s

c. The direction of puck B after the collision is:

$\theta _b=tan^{-1}\frac{v_{b2y}}{v_{b2x}}\\\\=tan^{-1} \frac{-6.052}{3.218}\\\\\approx 62\textdegree$

Hence, the direction of B's velocity after the collision is 62°

4 0

3 years ago

in a paragraph explain how electncity is generated at a power plant. please don't answer if you don't know

Anna [14]

Answer:

A turbine spins to generate electricity. There are many ways to spin the turbine by using water, steam, nuclear and so on.

3 0

3 years ago

I WILL MARK YOU AS BRAINLIEST IF RIGHT

butalik [34]

Answer:

25.4 miles per hour

Explanation:

speed=distance/time

speen=524/20.6 hours

=25.4 miles per hour

6 0

3 years ago

Five-gram samples of copper and aluminum are at room temperature. Both receive equal amounts of energy due to heat flow. The spe

hammer [34]

Answer:

<u><em>c. The copper will get hotter than the aluminum.</em></u>

Explanation:

The <em>energy due to heat flow</em>, i.e. the heat energy, is proportional to the product of the mass, the <em>specific heat capacity</em>, and the change in <em>temperature</em>:

$Heat=mass\times \text{specific heat capacity }\times\Delta T$

From which you obtain:

$\Delta T=\dfrac{Heat}{mass\times \text{specific heat capacity}}$

That equation tells that the change in temperature is inversely related to the product of the mass and the specific heat.

In the problem, the masses of the samples of copper and aluminum are equal (<em>5.00g</em>) and both samples receive <em>equal amounts of energy due to heat flow</em>, thus the only difference is the <em>specific heat capacity</em> of each sample.

From the above stated relationship between the change in temperature, the heat, the mass, and the specific heat capacity, under the assumption of all the other conditions equal (heat energy and mass), the higher the specific heat capacity the lower the change in temperature, and the lower the specific heat capacity the greater the change in temperature.

The heat capacity of copper (0.09 cal/g°C) is lower than the specific heat capacity of aluminum is (0.22 cal/g°C), thus the increase in temeperature of the copper sample will be greater than that of the aluminum sample. This means that <em>the copper will get hotter than the aluminum (option c.)</em>

5 0

3 years ago