Answer:
t=7.33 s
Explanation:
According to Newton's second law:

because we don't want the box to slide, the acceleration has to be zero.

we know that:

Now having the acceleration, we can use the following formula.

Answer: 
Explanation:
According to the described situation we have the following data:
Horizontal distance between lily pads: 
Ferdinand's initial velocity: 
Time it takes a jump: 
We need to find the angle
at which Ferdinand jumps.
In order to do this, we first have to find the <u>horizontal component (or x-component)</u> of this initial velocity. Since we are dealing with parabolic movement, where velocity has x-component and y-component, and in this case we will choose the x-component to find the angle:
(1)
(2)
(3)
On the other hand, the x-component of the velocity is expressed as:
(4)
Substituting (3) in (4):
(5)
Clearing
:

This is the angle at which Ferdinand the frog jumps between lily pads
Near the surface of reflection, reflected wave may interfere with incident wave leading to production of constructive and as well as destructive interference. This in turn, can result to resonance as well as enhancement of the sound intensity as the waves of reflection adds to incident wave. Therefore, the girl would higher intensity of reflected waves as compared to incident waves.
Therefore, statement A is correct.
Let's use the mirror equation to solve the problem:

where f is the focal length of the mirror,

the distance of the object from the mirror, and

the distance of the image from the mirror.
For a concave mirror, for the sign convention f is considered to be positive. So we can solve the equation for

by using the numbers given in the text of the problem:



Where the negative sign means that the image is virtual, so it is located behind the mirror, at 8.6 cm from the center of the mirror.
Answer:
D
Explanation:
Political scientists use political models to describe the political climate, which is an aggregate mood or opinion of a political society at a point in time.