The correct answer is:
<span>C) The actual frequency of the siren does not change despite appearances.
In fact, Bob will observe an increase in the apparent frequency as the emergency vehicle approaches him, while Jill will observe a decrease in the apparent frequency as the emergency vehicle moves away from him, because of the Doppler effect (the relative velocity between the observer and the source of the sound is changing), but this effect involves the apparent frequency, while the real frequency of the siren will remain the same.</span>
Answer:
5 no
Explanation:
actually the 4kg lying on table has no influence
it slides towards 4kg weight hung
as it has excess 2kg force
force=miu × m ×g
Answer:
(a) 32.5 kgm/s
(b) 32.5 Ns
(c) 10.8 N
Explanation:
The change in momentum can be calculated from the definition of linear momentum:
Then, the change in momentum of the body is of 32.5 kgm/s (a).
Now, from the impulse-momentum theorem, we know that the change in momentum of a body 
is equal to the impulse 
exerted to it. So, the impulse produced by the force equals 32.5 kgm/s (or 32.5 Ns) (b).
Finally, since we know the value of the impulse and the interval of time, we can easily solve for the magnitude of the force:
It means that the magnitude of the force is of 10.8N (c).
Answer:
current = 8,750
Explanation:
you will need to use the formula i = v/r to get this answer
I believe the correct answer is B.<span>positively charged hair.</span>
