Because the number of valence electrons of an element determines the properties and in particular the reactivity of that element.
In fact, elements of the first group (i.e. only one valence electron) have high reactivity, because they can easily give away their valence electron to atoms of other elements forming bonds. On the contrary, elements of the 8th group (noble gases) have their outermost shell completely filled with electrons, so they do not have valence electrons, and they have little or no reactivity at all.
Answer:
number 3 The wind because the wind has strong pressure which causes to change peoples directions in where they are going
Explanation:
hope this helped by the way i think you answered b and 4 i don't know if this is a test and i sent this at the wrong time :(
The equations are analogous to that for linear movement:
acceleration = (final velocity - initial velocity) / time
acceleration = (3000 rpm - 0 rpm) / 2.0 s
a) acceleration = 1500 rpm/s or 25 rp(s^2)
For the displacement
displacement = initial velocity*time + 0.5*acceleration*time^2
displacement = (0)*(2 s) + (0.5)(25 rps^2)*(2 s)^2
b) displacement = 50 revolutions
Answer:
Explanation:
The object is moving to and fro about its mean position
and the equation for its displacement is given as
now in one complete time period we know that the the object will complete its one oscillation
So the change in the position of the object in one complete time period will be ZERO
so here we can say that
since change in position is zero
so displacement = 0
A horizontal line means the object is. not changing its position it is not moving, it is at rest.
