Answer:
In general, a scientific law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a scientific theory.
Explanation:
Answer:
20.25 m
Explanation:
- <u>Centripetal acceleration </u>is given by; the square of the velocity, divided by the radius of the circular path.
That is;
<em><u>ac = v²/r</u></em>
<em> </em><em><u> Where; ac = acceleration, centripetal, m/s², v is the velocity, m/s and r is the radius, m</u></em>
Therefore;
r = v²/ac
= 27²/36
= 20.25 m
Hence the radius is 20.25 meters
To develop this problem it is necessary to apply the concepts related to Gravitational Potential Energy.
Gravitational potential energy can be defined as

As M=m, then

Where,
m = Mass
G =Gravitational Universal Constant
R = Distance /Radius
PART A) As half its initial value is u'=2u, then



Therefore replacing we have that,

Re-arrange to find v,



Therefore the velocity when the separation has decreased to one-half its initial value is 816m/s
PART B) With a final separation distance of 2r, we have that

Therefore




Therefore the velocity when they are about to collide is 
Answer:
option D
Explanation:
given.
horizontal velocity of arrow and a ball given as 50 m/s and 44 m/s respectively from the top of a building over flat ground.
In vertical direction, they are both identical
In vertical direction the initial velocity of arrow and a ball is 0 m/s
Their acceleration due to gravity is same for both arrow and a ball 9.8 m/s²
they will react bottom at the same time
time of flight is same for both
now,
In horizontal direction,
distance = speed × time
Since speed is more for arrow, it will travel more horizontal distance at the same time.
the correct answer is option D
<span>The formulas are,
v1d1² = v2d2² ........ (1)
h = (v2²-v1²)/2g ...... (2)
Given that,
v1 = 1.71 m/s
we assume that the stream has decreased by a factor
d2 =0.805d1
then,
v1d1² = v2 (0.805d1)²
cancelled both side d1² then we get,
v1 = v2 (0.805)²
v1 = v2 (0.648025)
Sub v1 = 1.71,
1.71 = v2 (0.648025)
v2 = 1.71/0.648025
v2 = 2.638787083831642
v2 = 2.64 m/s
The vertical distance formula,
h = (v2²-v1²)/2g
We know that value of gravity constant is 9.8 m/s²
h = {(2.64)² - (1.71)²)/2(9.8)
h = {(6.9696) - (2.9241)}/19.6
h = (4.0455)/19.6
h = 0.2064030612244898
h = 0.21 cm
Therefore, the vertical distance h = 0.21 cm.</span>