Answer:
The acceleration of the ball as it rises to the top of its arc equals 9.807 meters per square second.
Explanation:
Let suppose that maximum height of the arc is so small in comparison with the radius of the Earth.
Since the ball is launched upwards, then the ball experiments a free-fall motion, that is, an uniform accelerated motion in which the element is accelerated by gravity. Then, the acceleration experimented by the motion remains constant at every instant and position.
Besides, the gravitational acceleration in the Earth and, in consequence, the acceleration of the ball as it rises to the top of its arc equals 9.807 meters per square second.
The resultant or the net force act on the object cannot be 0. it must have a value but the direction is opposite from the object move direction.
if the object move to the left, so the net force or the resultant is doing to the right
The two different isotopes have weights :
w1 = 78.918 amu
w2 = 80.916 amu
average weight w3 = 79.903 amu
The mixing of two components can be modeled as
let the fraction of w1 be 'x'
hence 
now this is a linear equation in 'x'. Substituting the values we get
x = 0.507
hence the percentage of Br79 = 50.7% and the percentage of BR81 = 49.3%
Answer:
two-slit interference model was proposed by Young d sin θ = m λ
Explanation:
The two-slit interference model was proposed by Young, it establishes that if a coherent source of light passes through two slits, the shape of the given pattern is a consequence of the relative phase difference between the two rays; mathematically it can be expressed by
d sin θ = m λ
m= 0, 1, 2, 3, ...
for constructive interference, that is, the two rays arrive with a number between wavelengths.
D is the distance between the slits, tea the angle between the two rays, m an integer and m the wavelength used.
In a simulation a pattern of slits of equal intensity and equally spaced is observed.
Gravitational force pushes down on us to keep us on the ground. So it pushes in a downward direction.