Answer:
H = 171.90 m
Explanation:
given data
distance = 53.2 m
height = H
to find out
height H
solution
we know height is here H =
......................1
here t is time and a is acceleration
so
we find t first
we know during time (t -1) s , it fall distance (H - 53.2) m
so equation of distance


................2
now subtract equation 2 from equation 1 so we get
53.2 = gt - 
53.2 = 9.81 t - 
t = 5.92 s
so from equation 1
H =
H = 171.90 m
<span>Modern vehicles are designed to crush or crumple to absorb kinetic energy.</span>
Answer: 4.8 s
Explanation:
We have the following data:
the mass of the raft
the force applied by Sawyer
the raft's final speed
the raft's initial speed (assuming it starts from rest)
We have to find the time 
Well, according to Newton's second law of motion we have:
(1)
Where
is the acceleration, which can be expressed as:
(2)
Substituting (2) in (1):
(3)
Where 
Isolating
from (3):
(4)
Finally:
Answer:
m is expressed in kilograms and r in metres, with I (moment of inertia) having the dimension kilogram-metre square.
When two mechanical waves that have positive displacements from the equilibrium position meet and coincide, a constructive interference occurs.
Option A
<h3><u>
Explanation:</u></h3>
Considering the principle of superposition of waves; the resultant amplitude of an output wave due to interference of two or more waves at any point is given by individual addition of their amplitudes at that point. Two waves with positive displacements refer to the fact that crest of the both the waves are on the same side of displacement axis, either both are positive or both are negative, similarly with their troughs.
If such two waves with their crest on crest meet at any point, by superposition principle. their individual amplitude gets added up and hence the resultant wave after interference is greater in amplitude that both the individual waves. This is termed as a constructive interference. Destructive interference on the other hand is a condition when one of the two waves has a positive displacement and other has a negative displacement (a condition of one’s crest on other’s trough); resulting in amplitude subtraction.