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2 years ago

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Remember KE=M*V2/2…  A model airplane moves twice as fast as another identical model airplane. Compared with the kinetic energy

of the slower airplane, the kinetic energy of the faster airplane is

1 answer:

pishuonlain [190]2 years ago

4 0

Answer: 4 times as much

Explanation:

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After an ice storm, ice falls from one of the top floors of a 65-story building. The ice falls freely under the influence of gra

adell [148]

Answer:

The correct answer is a) The kinetic energy of the ice increases by equal amounts for equal distances.

Explanation:

The law of conservation states that the energy cannot be created nor be destroyed but can be converted from one form to another.Before the ice even starts falling we already know that it possesses energy in the form of potential energy given by P=mgh where m is the mass of the ice , g is the acceleration due to gravity and h is the height of the ice above the ground whatever that may be, since a number is not given here.As the ice falls the energy is converted from potential energy to kinetic energy. We notice one thing about the equation for the potential energy P , which is that it is not only directly proportional to h but also is linear in h as well(which is the main reason why a) is correct) which means that if the ice drops by 1 meter the potential energy it will have lost would be ΔPE=mgΔh=-mg, where Δh is the change in its height which is 1 meter here.And according to the principle of conservation of energy this energy must be converted to kinetic energy so the ΔKE=-ΔPE=mg, and this process repeats and for each meter it falls, it picks up the same amount of kinetic energy equaling mg(which is the same as the loss in PE per each meter of fall). So a 2 meter decrease in height will result in an increase in KE of 2mg, a 3 meter decrease in height will result in an increase in KE of 3mg. gain in kinetic energy only depends on the drop in height, which is true irrespective of where the ice might happen to be in its journey close to the top or the bottom. So the drop in height of lets say x at any point in the journey will result in the same increase in KE = ΔKE = mgx. Which proves part a) to be correct.

7 0

2 years ago

During a single-replacement reaction, a more-active metal will replace a less-active metal in a compound. Which single-replaceme

son4ous [18]

Answer:

Mg will replace Ag in a compound

Explanation:

A single replacement reaction is driven by the position of ions on the activity series.

As a rule of thumb, the position of metal ions on the activity series determines their reactivity.

Metal ions that are above another are more reactive and they will displace those that are lower.

Generally, activity increases as we go up the group.

Mg ions are higher than Ag ions on the series so, Mg will displace Ag from a solution.

8 0

2 years ago

How does the movement of particles of matter change when matter goes from solid to liquid? (1 point)

Y_Kistochka [10]

Answer: c

Explanation: because if it increases then it gets hotter

if it decreases then its getting colder.

3 0

2 years ago

An electron is held at a distance from a stationary, positively charged object.

salantis [7]

Answer:

A. Electric potential energy into kinetic energy

Explanation:

The electric potential energy of the charged particles is converted into kinetic energy as the electron is released.

5 0

2 years ago

Read 2 more answers

Phosphorous reacts with chlorine gas to produce phosphorous pentachloride. Calculate the mass of product produced when 25.0 g of

MariettaO [177]

Answer : The mass of product produced if the reaction occurred with a 70.5 percent yield will be, 20.67 grams.

Explanation : Given,

Mass of P = 25 g

Mass of $Cl_2$ = 25 g

Molar mass of P = 30.97 g/mole

Molar mass of $Cl_2$ = 71 g/mole

Molar mass of $PCl_5$ = 208.24 g/mole

First we have to calculate the moles of $P$ and $Cl_2$ .

$\text{Moles of }P=\frac{\text{Mass of }P}{\text{Molar mass of }P}=\frac{25g}{30.97g/mole}=0.807moles$

$\text{Moles of }Cl_2=\frac{\text{Mass of }Cl_2}{\text{Molar mass of }Cl_2}=\frac{25g}{71g/mole}=0.352moles$

Now we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

$2P+5Cl_2\rightarrow 2PCl_5$

From the balanced reaction we conclude that

As, 5 moles of $Cl_2$ react with 2 moles of $P$

So, 0.352 moles of $Cl_2$ react with $\frac{2}{5}\times 0.352=0.1408$ moles of $P$

That means, in the given balanced reaction, $Cl_2$ is a limiting reagent and it limits the formation of products and $P$ is an excess reagent because the given moles are more than the required moles.

Now we have to calculate the moles of $PCl_5$ .

As, 5 moles of $Cl_2$ react with 2 moles of $PCl_5$

So, 0.352 moles of $Cl_2$ react with $\frac{2}{5}\times 0.352=0.1408$ moles of $PCl_5$

Now we have to calculate the mass of $PCl_5$ .

$\text{Mass of }PCl_5=\text{Moles of }PCl_5\times \text{Molar mass of }PCl_5$

$\text{Mass of }PCl_5=(0.1408mole)\times (208.24g/mole)=29.32g$

Now we have to calculate the mass of product produced (actual yield).

$\%\text{ yield of }PCl_5=\frac{\text{Actual yield of }PCl_5}{\text{Theoretical yield of }PCl_5}\times 100$

$70.5=\frac{\text{Actual yield of }PCl_5}{29.32g}\times 100$

$\text{Actual yield of }PCl_5=20.67g$

Therefore, the mass of product produced if the reaction occurred with a 70.5 percent yield will be, 20.67 grams.

3 0

3 years ago