If you look on the periodic table you will see the top group elements depending on how the elements relate to each in the column. All of the elements in that column show they all have 1 electron in their valence shell. Some of the chemicals in that family or group are Sodium, Lithium, Potassium. The are very reactive because they only have one electron and what 7 more to become stable.
Explanation:
Let h is the height of the plane above ground. x is the horizontal distance between the ground and the airport. Let s(t) is the distance between the plane and the airport. So,
...........(1)
Given, h = 4, x = 40 and s(t) = -20 mph
Differentiate equation (1) wrt t


When x = 40, 



So, the speed of the airplane is 241.14 m/s. Hence, this is the required solution.
Answer:
v = 13.79 m/s
Explanation:
given,
mass of ball = 110 g
height = 11 m
ball is released from = 1.3 m
minimum speed = ?
using conservation of energy
Potential energy is conserved in the form of kinetic energy







v = 13.79 m/s
Bigger is the correct answer. the faster an igneous rock cools the bigger the bigger the crystal size will be
Answer:
y = 33.93 10⁵ m
Explanation:
This is an interference exercise, for the contributory interference is described by the expression
d sin θ = m λ
let's use trigonometry for the angle
tan θ = y / L
how the angles are small
tan θ = sin θ / cos tea = sin θ
we substitute
sin θ = y / L
d y / L = m λ
y = m λ L / d
the light fulfills the relation of the waves
c = λ f
λ = c / f
λ = 3 10⁸ /375
λ = 8 10⁵ m
first order m = 1
let's calculate
y = 1 8 10⁵ 4030 10-9 / 950 10-9
y = 33.93 10⁵ m