Answer:
Explanation:
Width of central diffraction peak is given by the following expression
Width of central diffraction peak= 2 λ D/ d₁
where d₁ is width of slit and D is screen distance and λ is wave length.
Width of other fringes become half , that is each of secondary diffraction fringe is equal to
λ D/ d₁
Width of central interference peak is given by the following expression
Width of each of bright fringe = λ D/ d₂
where d₂ is width of slit and D is screen distance and λ is wave length.
Now given that the central diffraction peak contains 13 interference fringes
so ( 2 λ D/ d₁) / λ D/ d₂ = 13
then ( λ D/ d₁) / λ D/ d₂ = 13 / 2
= 6.5
no of fringes contained within each secondary diffraction peak = 6.5
The food package will strike the ground at 11 degrees below the horizontal.
<h3>Time for the food package to hit the ground</h3>
The time for the food package to hit the ground is calculated as follows;
h = vt + ¹/₂gt²
<em>let the initial velocity be horizontal</em>
4900 = 0(t) + (0.5 x 9.8)t²
4900 = 4.9t²
t² = 4900/4.9
t² = 1,000
t = √1,000
t = 31.62 s
<h3> Final speed of the food package when it hits ground</h3>
vf(y) = vo + gt
vf(y) = 0 + (31.62 x 9.8)
vf(y) = 309.88 m/s
<h3>Angle of projection</h3>
The horizontal component of the speed will be constant, while vertical component will change

Angle below the horizontal = 90 - 79 = 11⁰
Thus, the food package will strike the ground at 11 degrees below the horizontal.
Learn more about angle of projection here: brainly.com/question/10671136
Answer:
W = 650 [kJ]
Explanation:
The definition of work is denoted by the product of force by the distance traveled by the body, this distance traveled corresponds to the direction of the force.
In this case we have:
d = distance = 2.6[km] = 2600 [m]
F = force = 250 [N]
W = F*d = 250 * 2600 = 650000 [J] or 650 [kJ]
let the distance of pillar is "r" from one end of the slab
So here net torque must be balance with respect to pillar to be in balanced state
So here we will have

here we know that
mg = 19600 N
Mg = 400,000 N
L = 20 m
from above equation we have



so pillar is at distance 10.098 m from one end of the slab