Starting from the angular velocity, we can calculate the tangential velocity of the stone:
Then we can calculate the angular momentum of the stone about the center of the circle, given by
where
m is the stone mass
v its tangential velocity
r is the radius of the circle, that corresponds to the length of the string.
Substituting the data of the problem, we find
To develop this problem we will apply the concepts related to the Doppler effect. The frequency of sound perceive by observer changes from source emitting the sound. The frequency received by observer 
is more than the frequency emitted by the source. The expression to find the frequency received by the person is,
= Frequency of the source
= Speed of sound
= Speed of source
The velocity of the ambulance is
Replacing at the expression to frequency of observer we have,
Therefore the frequency receive by observer is 878Hz
Answer:
The two correct answers are B.) reacting quickly with water, and D.) forming bonds with other atoms.
Explanation:
Answer:
All the observers are correct.
Explanation:
This is simply a problem of reference frames from which the motion of the book is being viewed by the various observers.
From their various reference frames, they are all correct.
Observer A must be in the inertial reference frame.
<em>Observers who can explain the behavior of the book and the car by using the relationship between the sum of the forces and changing velocity are said to be observers in inertial reference frames.</em>
This is clearly shown by what observer A noticed. There was a relative motion between the book and the car as she pointed out, making her to be in an inertial reference frame.
<em>Similarly, observers in inertial reference frames can also explain the changes in velocity of objects by considering the forces exerted on them by other objects.</em>
This is shown by observer B as he is able to notice how the force of the car affects the velocity of the book.
Observer C is actually in a non-inertial reference frame, as newtons law of force motion relationship are no longer observed. This occurs in the non inertial reference frame.
