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.
Answer:
in first case the torque is maximum.
Explanation:
Torque is defined as the product of force and the perpendicular distance.
τ = F x d x Sinθ
In case A: the angle between force vector and the distance vector is 90 so torque is
τ = F x d
In case B: the angle between force vector and the distance is 30°.
τ = F x d x Sin30
τ = 0.5 Fd
So the torque is maximum in first case.
Answer:
C) No work is required to move the negative charge from point A to point B.
Explanation:
An equipotential surface is defined as a surface connecting all the points at the same potential.
Therefore, when a charge moves along an equipotential surface, it moves between points at same potential.
The work done when moving a charge is given by
where
q is the charge
is the potential difference between the initial and final point of motion of the charge
However, the charge in this problem moves along an equipotential surface: this means that the potential does not change, so
And so, the work done is also zero.
The lower the frequency the lower the pitch sound.
Answer:
t = 0.437 s
Explanation:
The speed of sound is a constant that is worth v = 343 m / s
v = d / t
t = d / v
the time it takes for the sound to reach Clark at d = 150 m is
t = 150/343
t = 0.437 s
This same sound takes much longer to reach you
t₂ = 127 10³/343
t₂ = 370 s
