Answer:
Sound travels faster in liquids than in gases because molecules are packed more closely together. This means that when the water molecules begin to vibrate, they quickly begin to collide with each other forming a rapidly moving compression wave. Sound travels over four times faster than in air
Explanation:
Answer:
120 N
Explanation:
F=ma therefore 60kg times 2m/s^2 is 120 N
D=Vot+1/2at^2
In this case, there is no initial y velocity so the term Vot=0 so d=1/2at^2
acceleration=acceleration due to gravity=-9.8m/s^2
It falls - 22cm or -0.22m
We have - 0.22=1/2(-9.8)t^2
t^2=(-0.44)/(-9.8)
t=sqrt[0.44/9.8]
For the first one, the correct answer would be "<span>Substance changes its form but not its molecular composition.". During a physical change (let's say cutting paper), the substance has its shape changed, but it is still itself (paper).
</span><span>The second one is a bit trickier: </span>
Kinetic energy of a molecule is directly influenced by temperature. If there is a higher temperature it will have a higher kinetic energy which means the molecule moves at a higher velocity. This will increase the chance of particles bouncing off of each other during the chemical reaction. That explains why the rate of reaction will be higher at a higher temperature, rather than higher at a cool temperature. The correct answer would be lower at 39F.
Answer:
Option B: change the objective lens
Explanation:
The revolving nosepiece is one of the parts of a microscope. Its responsibility is to hold the objective lenses.
