Does any part of our body vibrate when we speak ? name the part

When YOU speak, YOUR vocal cords vibrate, sending sound waves through the air and causing MY ear drums to vibrate.

When I speak, MY vocal cords vibrate, sending sound waves through the air an causing YOUR ear drums to vibrate.

carla slowed down in the beginning of her trip, stopped, and then sped up

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.