Answer:
Plasma is by far the most common form of matter. Plasma in the stars and in the tenuous space between them makes up over 99% of the visible universe and perhaps most of that which is not visible. On earth we live upon an island of "ordinary" matter.
Answer:
Explanation:
Given
length of window
time Frame for which rock can be seen is
Suppose h is height above which rock is dropped
Time taken to cover
so using equation of motion
where y=displacement
u=initial velocity
a=acceleration
t=time
time taken to travel h is
Subtract 1 and 2 we get
and from equation
so
and
so
substitute the value of in equation 2
Answer:
an open system
Explanation:
which is contrasted with the concept of an isolated system which exchanges neither energy, matter, nor information with its environment.
Forces are exerted I believe : all of the above
The action force might be Tyler throwing the ball
I don't know the last one
Answer:
the acceleration of the girl is 8 m/s² in opposite direction.
Explanation:
Given;
mass of the girl, m₁ = 30kg
mass of the boy, m₂ = 40 kg
acceleration of the boy, a₂ = 6 m/s²
let acceleration of the girl = a₁
Apply Newton's third law of motion;
the force exerted by the girl is equal in magnitude to the force exerted by the boy but in opposite direction.
F₁ = -F₂
m₁a₁ = -m₂a₂
30a₁ = -(40 x 6)
30a₁ = -240
a₁ = -240 / 30
a₁ = -8 m/s² (the negative sign shows that the acceleration is in opposite direction)
Thus, the acceleration of the girl is 8 m/s² in opposite direction.