Megahertz is a measurement of

Correct Answer: dark surfaces

Explanation:

Albedo refers to a material's ability to reflect sunlight. Since 30% of the sun's energy is reflected by the entire earth, the earth has an average albedo of 0.30.

Generally, dark surfaces have a low albedo and light surfaces have a high albedo.

Correct Answer: Heterogeneous

Explanation:

Blood is a heterogeneous mixture because the blood cells are physically separate from the blood plasma. The cells have different properties than the plasma. The cells can be separated from the plasma by centrifuging, which is a physical change.

Correct Answer: Wind

Explanation:

The energy sources that are constantly being replenished, such as sunlight, wind, and water. This means that we can use them as much as we want, and we do not have to worry about them running out. Additionally, renewable energy sources are usually much more environmentally friendly than fossil fuels. Overall, they release very few chemicals, like carbon dioxide, that can harm the environment.


Most of this energy comes from fossil fuels, such as coal, oil, and natural gas. These are nonrenewable energy sources, which means that if we use them all up, we can never get more during our lifetime. Fossil fuels also contribute greatly to global climate change by releasing carbon dioxide into the air when they are burned.

Correct Answer: 0

Explanation:

No work done as there is no external external pressure in free expansion. 

 

Hence, Work done in a free expansion process is Zero.

Correct Answer: homogeneous

Explanation:

A Mixture is a material made up of two or more different substances which are mixed.

 

Mixtures can be either homogeneous or heterogeneous.

 

* A homogeneous mixture is a type of mixture in which the composition is uniform and every part of the solution has the same properties.

* A heterogeneous mixture is a type of mixture in which the components can be seen, as there are two or more phases present.

 

Air is a homogeneous mixture of the gaseous substances nitrogen, oxygen, and smaller amounts of other substances.

Correct Answer: for cleaning procedures

Correct Answer: energy can neither be created nor destroyed

Explanation:

The law of conservation of energy is a law of science which states that energy can neither be created nor destroyed - only converted from one form of energy to another.

In 1842, Julius Robert Mayer discovered the Law of Conservation of Energy.

Correct Answer: All of the above

Explanation:

The strength of an electromagnet can be increased by increasing the cross-sectional area, increasing the number of turns, increasing current supply, increasing the length of the coiled wire.

 

Correct Answer: Solids

Explanation:

We know that, in solids all the particles are packed together and hence sound can travel from one to one very fast.

 

Hence, speed of sound is maximum in solids and decreses from solids to liquids and liquids to gases. Sound can't travel through vaccum.

Correct Answer: All of the above

Explanation:

The highly energetic gamma particles can penetrate most compounds that stop by other types of radiation. However, lead, steel, or concrete can reduce the high energy of these particles, making them less penetrating.

 

Hence, Gamma radiation can be stopped by a several inches of lead or steel, or several meters of concrete.