All categories

3 years ago

Hermal energy is a form of... A. Potential energy. B. Kinetic energy. C. Chemical energy.

Physics

1 answer:

aev [14]3 years ago

6 0

Thermal energy also known as 'heat energy' is a form of kinetic energy.

You might be interested in

Which of these forces pull or push upward, and which pull or push downward? Explain.

PtichkaEL [24]

Answer:

A force is a push or pull that acts upon an object as a result of that objects interactions

Explanation:

8 0

3 years ago

Which explains why light bends when it passes from air to water?

Serggg [28]

Answer: D
Key thing to keep note, is "refraction"...
Look at some experiments on YouTube, it's helps me a lot.

4 0

3 years ago

Read 2 more answers

Which of the following is the most accurate statement concerning the properties of matter?

DIA [1.3K]

Answer:

b. they can be observed and measured

Explanation:

Matter is anything that has weight and occupy space. There are three states of matter namely Solid, liquid and gas.

The properties of matter are both physical and chemical in nature. Both properties can be measured and observed. Phhysical properties are anything that can be measured without changing the state of the matter. Example of physical properties includes mass, volume, length, color etc.

Chemical properties is another properties of matter. This is the ability of the states of matters to combine with other substance to form a new product for example, rusting of iron, formation of salt etc.

All this as discussed are both measurable and can be observed.

8 0

4 years ago

Is cordyceps fungi a predator? If not, what is it?

ASHA 777 [7]

Answer:

It is a predator.

Explanation:

They eat other insects so therefore I think they're a predator.

5 0

3 years ago

According to Archimedes’ principle, the mass of a floating object equals the mass of the fluid displaced by the object. Use this

e-lub [12.9K]

Answers:

a) $\rho_{cylinder}= 0.55 g/cm^{3}$

b) $\rho_{liq}= 1.48 g/cm^{3}$

c) When we divided both volumes (sumerged and displaced) the factor $\pi r^{2}$ is removed during calculations.

Explanation:

a) According to Archimedes’ Principle:

A body totally or partially immersed in a fluid at rest, experiences a vertical upward thrust equal to the mass weight of the body volume that is displaced.

In this case we have a wooden cylinder floating (partially immersed) in water. This object does not completely fall to the bottom because the net force acting on it is zero, this means it is in equilibrium. This is due to Newton’s first law of motion, that estates if a body is in equilibrium the sum of all the forces acting on it is equal to zero.

Hence:

$W_(cylinder)=B$ (1)

Where:

$W_(cylinder)=m.g$ is the weight of the wooden cylinder, where $m$ is its mass and $g$ gravity.

$B$ is the Buoyant force, which is the force the fluid (water in this situation) exert in the submerged cylinder, and is directed upwards.

We can rewrite (1) as follows:

$m_{cylinder}g=m_{water}g$ (2)

On the other hand, we know density $\rho$ establishes a relationship between the mass of a body andthe volume it occupies. Mathematically is expressed as:

$\rho=\frac{m}{V}$ (3)

isolating the mass:

$m=\rho V$ (4)

Now we can express (2) in terms of the density and the volume of cylinder and water:

$\rho_{cylinder} V_{cylinder} g=\rho_{water} V_{water} g$ (5)

In this case $V_{water}$ is the volume of water displaced by the wooden cylinder (remembering Archimedes's Principle).

At this point we have to establish the total volume of the cylinder and the volume of water displaced by the sumerged part:

$V_{cylinder}=\pi r^{2} h$ (6)

Where $r$ is the radius and $h=30 cm$ the total height of the cylinder.

$V_{water}=\pi r^{2} (h-h_{top})$ (7)

Where $h_{top}=13.5 cm$ is the height of the top of the cylinder above the surface of water and $(h-h_{top})$ is the height of the sumerged part of the cylinder.

Substituting (6) and (7) in (5):

$\rho_{cylinder} \pi r^{2} h g=\rho_{water} \pi r^{2} (h-h_{top}) g$ (8)

Clearing $\rho_{cylinder}$ :

$\rho_{cylinder}=\frac{\rho_{water}(h-h_{top})}{h}$ (9)

Simplifying;

$\rho_{cylinder}=\rho_{water}(1-\frac{h_{top}}{h}$ (10)

Knowing $\rho_{water}=1g/cm^{3}$ :

$\rho_{cylinder}=1g/cm^{3}(1-\frac{13.5 cm}{30cm})$ (11)

$\rho_{cylinder}= 0.55 g/cm^{3}$ (12) This is the density of the wooden cylinder

b) Now we have a different situation, we have the same wooden cylinder, which density was already calculated ( $\rho_{cylinder}= 0.55 g/cm^{3}$ ), but the density of the liquid $\rho_{liq}$ is unknown.

Applying again the Archimedes principle:

$\rho_{cylinder} V_{cylinder} g = \rho_{liq} V_{liq} g$ (13)

Isolating $\rho_{liq}$ :

$\rho_{liq}= \frac{\rho_{cylinder} V_{cylinder}}{V_{liq}}$ (14)

Where:

$V_{cylinder}=\pi r^{2} h$

$V_{liq}=\pi r^{2} (h-h_{top})$

Then:

$\rho_{liq}= \frac{\rho_{cylinder} \pi r^{2} h}{\pi r^{2} (h-h_{top})}$ (15)

$\rho_{liq}= \frac{\rho_{cylinder} h}{h-h_{top}}$ (16)

$\rho_{liq}= \frac{0.55 g/cm^{3} (30 cm)} {30 cm - 18.9 cm}$ (17)

$\rho_{liq}= 1.48 g/cm^{3}$ (18) This is the density of the liquid

c) As we can see, it was not necessary to know the radius of the cylinder (we did not need to knoe its length and width), we only needed to know the part that was sumerged and the part that was above the surface of the liquid.

This is because in this case, when we divided both volumes (sumerged and displaced) the factor $\pi r^{2}$ is removed during calculations.

6 0

4 years ago