What is 3780 cal to kJ

Answer:

B. Knowing the color and brightness of a star

Explanation:

Answer:

According to significant figures we have leading zeros, trapped zeros and zeros at the beginning. So that number is a leading zeros and its has 7 SGF.

Explanation:

The 2019 water crisis in Chennai has made us realize the importance of saving water more than ever. Water, as we all know, is a finite resource without which our planet would be a barren wasteland. Today with our increasing population it would be logical to say that our water consumption has also increased. And with increasing demand and lesser supply, water scarcity arises. Our ancestors who had foreseen the potential dangers of water scarcity had developed methods to conserve water that was suited for the varied terrain of the Tamil-speaking kingdoms.

Traditional Rainwater Conservation methods of Tamil Nadu

Eri

There are no perennial rivers in Tamil Nadu except the Thamirabharani River which flows through Thirunelveli district. And so, several hundred years ago a simple system was devised to utilize the rainwater to the fullest. An Eri or tank system is one of the oldest forms of water conservation systems in India. Many Eris are still in use in Tamil Nadu and play an active role in irrigation. They act as water reservoirs and flood control systems. They prevent soil erosion, recharge groundwater, and prevent wastage of runoff water during heavy rainfall.

Kudimaramathu

Kudimaramathu is one of the old traditional practice of stakeholders participating in the maintenance and management of irrigation systems. During earlier days, citizens of a village used to actively participate in maintaining the water bodies of their village by deepening and widening the lakes and ponds and restoring the water bodies back to their original form. The silt, rich in nutrients, collected in the process would be used by the farmers themselves in their field. A sense of collective ownership ensured the continued survival of the water bodies.

Answer:  0.050 moles of NaOH

Explanation:  The molar mass of NaOH is 40.0g/mole

2.0g/40.0g/mole  =  0.050 moles (2 sig fig)

Answer:

it's a property of a cell, tissue and organisms that allows to maintain and regulate the stability and constancy to function properly

Answer:

The elements of Group VIIA (new Group 17 – fluorine, chlorine, bromine, iodine, and astatine) are called the halogens (tan column). The term “halogen” means “salt-former” because these elements will readily react with alkali metal and alkaline earth metals to form halide salts

Answer:

Objects that can emit light energy by themselves are known as luminous objects. Objects that cannot emit light energy by themselves are known as non-luminous objects.

Explanation:

Explanation:

Luminous objects:- The objects that can emit light energy by themselves are known as luminous objects.

Objects like the sun that give out or emit light of their own are luminous objects.

Other examples of luminous bodies are Electric bulb, torch etc.

Non-luminous objects:- the objects that can not emit light energy by themselves are known as Non- luminous objects.

Objects like the moon that do not give out or emit light of their own are Non- luminous objects.

Moon is an example of a non-luminous object as we can see the moon because it reflects light from the sun.

Other examples of Non luminous bodies are pen, pencil, chair, wood etc.

Luminosity – It is defined as the luminous intensity in a particular direction; or we can say it is the apparent brightness of an image.

The brightness of a star is defined as the total energy radiated in unit time. It is related to the surface area (A) and the effective temperature (TT) ( the temperature of a black body having the same radius as the star and radiating the same amount of energy per unit area in one second ) by a form of Stefan’s law, here is given by

⇒L=AσT4⇒L=AσT4

where 

σ is the Stefan’s constant and L is the luminosity.

Note:

The laptop screen, mobile screen you are looking at right now is luminous but the page of your book is a non-luminous object, which is why you need a light on to read it.

Explanation:

Answer:

Because.in theory, it's impossible for philosophers (Greeks) don't have the proper equipment and also they don't have enough facts to back it up

Explanation:

Hope this helps

Answer:

See explanation below for answers

Explanation:

0.00305

0.00310

0.00300

0.00305

0.00305

When there is a decimal point, you must skip the zeros until you reach a number. Once you reach that number, you move 2 more places to the right of that number in order to have 3 significant figures. Hope this helps!

Answer:

The choose 2. H2O , HCN

I hope I helped you^_^

Answer:

one unit to the left

Explanation:

cm are 10 times mm, so to convert you have to divide by ten

Examples

100 mm = 10,0 cm

0.50 mm = 0.05 cm

Answer:

Gas

Explanation:

The atoms, ions, or molecules that make up the gas are further apart and move freely at high speeds and is can easily be compressible.

Answer:

Gas

Explanation:

A gas is a substance or matter in a state in which it will expand freely to fill the whole of a container' having no shape like a solid and no fixed volume like a liquid.

Answer:

law

Explanation:

it is called a scientific law

Answer:

7. A. properties that differ from both iron and oxygen

8. D. cool the rod and heat the cylinder

9. B. sea level to a mountain top

Answer:

platinum is the correct answer

Answer:

it would be made of platinum

Explanation:

Answer:

[tex]{ \sf{Pb(NO_{3})_{2(aq)} + 2NaCl _{(aq)} → 2NaNO_{3(aq)} + PbCl _{2(s)} }} \\ [/tex]

Answer:

40.0 L

Explanation:

The formula to find the new pressure: [tex]\frac{P_1V_1}{T_1} = \frac{P_2V_2}{T_2}[/tex]

P₁ = 15.0 L

V₁ = 2 atm

T₁ = 300 K (Convert Celsius to Kelvin by adding 273)

P₂ = 1

V₂ = ?

T₂ = 400 K

[tex]\frac{(2)(15)}{300} = \frac{P_2(1)}{400}[/tex]

[tex]\frac{30}{300} = \frac{P_2}{400}[/tex]

[tex]\frac{1}{10} = \frac{P_2}{400}[/tex]

Multiply both sides by 400 to isolate the P₂

[tex]\frac{400}{10} = P_2[/tex]

[tex]P_2 = 40[/tex]

Option B, Metals have good conductivity.

Hope it helps you.. pls mark brainliest if it helps you

Answer:

Bromine is a dark reddish-brown fuming liquid with a pungent odor. Denser than water and soluble in water. Hence sinks in water.

Answer:

C

Explanation:

it would be the best action because questions are important when looking at designs/creating them.

Answer:

volume = l x h x w

this is just like your cylinder question. none of the answers represent the equation. sorry

Answer:

[tex]{ \underline{ \sf{solubility}}}[/tex]

Answer:I dunno

Explanation:it is the best thing I ever said in this app

Answer

50 N

Explanation

Answer:The answer is in the attached file below

Explanation: