Yeah what is the question
Answer: ice is less dense than liquid water. If ice was more dense, Earth would freeze.
Explanation: There are many reasons why life on Earth depends on the characteristics of water. One could discuss hydrogen bonds and its role as a solvent, but the unusual property of water is is the change in density with change in temperature. Water is densest at 4 degC, which is why ice floats - it is less dense than cold water (it melts quickly in warm water, so density isn’t impotant at higher temperatures). Most liquids are less dense than the solid, frozen form. If this was the case with water, any ice that formed would sink, and sease would freeze from the bottom up. Furthermore, the lowest layers would be insulated and would not all melt in summer. Thus over time, the seas would become a thin layer of liquid water at best, over solid ice. Life could not develop without liquid seas. In addition, ice is reflective, reducing the amount of sunlight absorbed, further reducing temperatures. Without ocean circulation, polar areas would be even colder, and there would be no rain.
Answer:
d. Radio wave
Explanation:
There are three types of mechanical waves, transverse waves, longitudinal waves, and surface waves
Answer: Option D is correct.
Explanation: Equation given by de Broglie is:
where, = wavelength of the particle
h = Planck's constant
m = mass of the particle
v = velocity of the particle
In option A, football will have some mass and is moving with a velocity of 25 m/s, hence it will have some wavelength.
In Option B, unladen swallow also have some mass and is moving with a velocity of 38 km/hr, hence it will also have some wavelength.
In Option C, a person has some mass and is running with a velocity of 7 m/hr, hence it will also have some wavelength.
As, the momentum of these particles are large, therefore the wavelength will be of small magnitude and hence, is not observable.
From the above, it is clearly visible that all the options are having some wavelength, so option D is correct.
Answer:
Your coefficients (the numbers in front of the molecule) will be the following from left to right.
1. <u>1 - 2 - 1 - 2</u>
2. <u>2 - 1 - 2 - 2 - 1</u>
3. <u>2 - 4 - 1</u>
4. <u>2 - 4 - 3</u>
5. <u>2 - 2 - 2 - 1</u>
6. <u>1 - 1 - 1</u>
7. <u>2 - 1 - 2</u>
8. <u>3 - 1 - 2 - 3</u>
9. <u>3 - 1 - 2 - 3</u>
10. <u>2 - 1 - 1 - 1</u>
Explanation:
To balance this equations first count how many times an element is on each side and then see what needs to be changed in order to balance them.