Answer:
1.16 Hz
Explanation:
frequency, basically, is the number of wave on 1 second
so, in math we write like this
f = n/t
n = number of waves
t = time to do that (in sec)
f = 140/120 = 7/6 Hz
f = 1.16 Hz
Answer:
20 J
Explanation:
Given:
Weight of the book is, 
Height or displacement of the book is, 
The work done on the book to raise it to a height of 2 m on a shelf is against gravity. The gravitational force acting on the book is equal to its weight. Now, in order to raise it, an equal amount of force must be applied in the opposite direction.
So, the force applied by me should be equal to weight of the body and in the upward direction. The displacement is also in the upward direction.
Now, work done by the applied force is equal to the product of force applied and displacement of book in the direction of the applied force.
Therefore, work done is given as:

Therefore, the work done to raise a book to a height 2 m from the floor is 20 J.
-- From January 15 to February 6 is a period of 22 days.
-- The period of the full cycle of moon phases is 29.53 days.
-- So those dates represent (22/29.53) = 74.5% of a full cycle of phases.
-- That's almost exactly 3/4 of a full cycle, so on February 6, the moon would be almost exactly at <em>Third Quarter</em>. That's the <em>left half of a disk </em>(viewed from the northern hemisphere).
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