Answer:
C
Explanation:
Light with energy above a certain point can be used to knock electrons loose, freeing them from a solid metal surface, according to Scientific American.
photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material
Answer:
D=387.28m
Explanation:
At the moment where the toss is made
, so we need both equations:
For the red car:
With initial speed of 0 and acceleration of 6.12m/s^2.
For the green car:
With
and Xo = 200m
Since both positions will be the same:
Solving for t:
t1 = -5.8s and t1 =11.25s
Replacing t = 11.25 on either equation to find the displacement:

Answer:
The acceleration of
is 
Explanation:
From the question we are told that
The mass of first block is 
The angle of inclination of first block is 
The coefficient of kinetic friction of the first block is 
The mass of the second block is 
The angle of inclination of the second block is 
The coefficient of kinetic friction of the second block is 
The acceleration of
are same
The force acting on the mass
is mathematically represented as

=> 
Where T is the tension on the rope
The force acting on the mass
is mathematically represented as


At equilibrium

So

making a the subject of the formula

substituting values 
=> 
Answer:
There are five signs of a chemical change:
Color Change.
Production of an odor.
Change of Temperature.
Evolution of a gas (formation of bubbles)
Precipitate (formation of a solid)
Explanation:
I just went ahead and gave you the five signs of chemical change hoped it helped
Choice D). is on the right track, but it's stated incorrectly.
The wavelengths of light coming from a galaxy that's moving toward us <em>are </em>
<em>shorter</em> than they were when they left the galaxy. When we see them, they're
shorter than they should be.
(This is called a "blue shift" in the spectrum of the galaxy, because blue is the
short-wavelength end of the spectrum of visible light. If the wavelength of some
light somehow becomes shorter, then the color of the light changes toward the
direction of blue.)
If the source of light is moving toward us, then the wavelength we see is shorter
than it should be. If the source is moving away from us, then the wavelength
we see is longer than it should be. The whole trick to this is knowing <u>what</u> the
wavelength of the light we see <em>should be</em> !