Answer:
Right
Explanation:
electromagnetic waves can travel through space (a vacuum) because it doesn't need a medium and its particles to propagate whereas a mechanical wave needs a medium to propagate. For example sound is a mechanical wave, sound vibrates off a mediums particles to propagate and for sound to be heard and travel
Answer:
lives, forces and motion make things move and stay still. Pushing and pulling are examples of forces that can sped things up or slow things down. There are two types of forces, at a distance force and contact forces..
Answer:
upwards
downwards
Explanation:
Given:
weight of the person, 
So, the mass of the person:



- Now if the apparent weight in the elevator,

<u>Then the difference between the two weights is :</u>


is the force that acts on the body which generates the acceleration.
Now the corresponding acceleration:


upwards, because the normal reaction that due to the weight of the body is increased here.
- Now if the apparent weight in the elevator,

<u>Then the difference between the two weights is :</u>


is the force that acts on the body which generates the acceleration.
Now the corresponding acceleration:


downwards, because the normal reaction that due to the weight of the body is decreased here.