Answer:
The fireman will continue to descend, but with a constant speed.
Explanation:
In kinetic friction <em>(which is the case discussed here) </em>since the fireman is already in motion because of a certain force, once the frictional force matches the normal force, the fireman will stop accelerating and continue moving at a constant rate with the original speed he had. We will need a force greater than the normal force acting on the fireman to cause a deceleration.
We need to understand the difference between static friction and kinetic friction.
Static friction occurs in objects that are stationary, while kinetic friction occurs in objects that are already in motion.
In static friction, when the frictional force matches the weight or normal force of the object, the object remains stationary.
While in kinetic friction, when the frictional force matches the normal force, the object will stop accelerating. This is the case of the fireman sliding down the pole as discussed above.
<u>Answer</u>
8. 2 Hz
9. 0.5 seconds
10. 20 cm
<u>Explanation</u>
<u>Q 8</u>
Frequency is the number of oscillation in a unit time. It is the rate at which something repeats itself in a second.
In this case, the spring bob up and down 2 times per second.
∴ Frequency = 2 Hz
<u>Q 9</u>
Period is the time taken to complete one oscillation.
2 oscillations takes 1 second
1 oscillation = 1/2 seconds.
∴ Period = 0.5 seconds
<u>Q 10</u>
Amplitude is the the maximum displacement of the spring.
In this case the spring bob up 20 cm. This is it's displacement.
∴ Amplitude = 20 cm
The answer would be c because it is talking about she wants to be in a good neighborhood
Answer:
Length of the pipe = 53.125 cm
Explanation:
given data
harmonic frequency f1 = 800 Hz
harmonic frequency f2 = 1120 Hz
harmonic frequency f3 = 1440 Hz
solution
first we get here fundamental frequency that is express as
2F = f2 - f1 ...............1
put here value
2F = 1120 - 800
F = 160 Hz
and
Wavelength is express as
Wavelength = Speed ÷ Fundamental frequency ................2
here speed of waves in air = 340 m/s
so put here value
Wavelength =340 ÷ 160
Wavelength = 2.125 m
so
Length of the pipe will be
Length of the pipe = 0.25 × wavelength ......................3
put here value
Length of the pipe = 0.25 × 2.125
Length of the pipe = 0.53125 m
Length of the pipe = 53.125 cm