Answer:
D. Radar uses radio, and the siren uses sound waves.
Explanation:
The main difference between the siren passing by and the radar is that radar uses radio waves and siren uses sound waves.
- Sound waves are mechanical waves which requires a material medium for their propagation.
- In a vacuum, the sound waves cannot pass through freely.
- Radar is an electromagnetic wave.
- It is particular of radio waves origin.
- Such waves do not require a material medium for their propagation and hence can be transmitted through a vacuum.
Answer:
The mass will be 90.91 kilograms, we can’t figure out the weight without knowing how much gravity is on the other planet.
Explanation:
Mass is the amount of substance a matter contains. The more the substance a matter contains, the more massive it becomes. The mass of an object is the same everywhere in the universe. Therefore, the cube will have the same mass of 90.91Kg in another planet.
Weight is a function of mass and the force of gravity on such a body. The weight of a body relies on the prevailing acceleration due to gravity in a particular place. Some places have gravity higher than that on earth and so they will have more weight. This is why we can't figure out weight without knowing the gravity in the other planet.
Answer:
Explanation:
The products of a chemical reaction have different properties than the reactant because they underwent a chemical change by definition of a chemical reaction. The products are new combinations atoms forming different molecules.
The main function is to help them see with all their eyes.
