Answer: 30.34m/s
Explanation:
The sum of forces in the y direction 0 = N cos 28 - μN sin28 - mg
Sum of forces in the x direction
mv²/r = N sin 28 + μN cos 28
mv²/r = N(sin 28 + μcos 28)
Thus,
mv²/r = mg [(sin 28 + μ cos 28)/(cos 28 - μ sin 28)]
v²/r = g [(sin 28 + μ cos 28)/(cos 28 - μ sin 28)]
v²/36 = 9.8 [(0.4695 + 0.87*0.8829) - (0.8829 - 0.87*0.4695)]
v²/36 = 9.8 [(0.4695 + 0.7681) / (0.8829 - 0.4085)]
v²/36 = 9.8 (1.2376/0.4744)
v²/36 = 9.8 * 2.6088
v²/36 = 25.57
v² = 920.52
v = 30.34m/s
Clever problem.
We know that the beat frequency is the DIFFERENCE between the frequencies of the two tuning forks. So if Fork-A is 256 Hz and the beat is 6 Hz, then Fork-B has to be EITHER 250 Hz OR 262 Hz. But which one is it ?
Well, loading Fork-B with wax increases its mass and makes it vibrate SLOWER, and when that happens, the beat drops to 5 Hz. That means that when Fork-B slowed down, its frequency got CLOSER to the frequency of Fork-A ... their DIFFERENCE dropped from 6 Hz to 5 Hz.
If slowing down Fork-B pushed it CLOSER to the frequency of Fork-A, then its natural frequency must be ABOVE Fork-A.
The natural frequency of Fork-B, after it gets cleaned up and returns to its normal condition, is 262 Hz. While it was loaded with wax, it was 261 Hz.
Answer:
3600N
Explanation:
Given: m = 1200kg, Vo = 0m/s, Vf = 30m/s, Δt = 10s
ΣF = ma
we need to find 'a' first, using the definition of 'a' we get equation:
a = (Vf-Vo)/Δt
a = (30m/s)/10s
a = 3 m/s^2
now substitute into top equation
ΣF = ma
Fengine = (1200kg)(3m/s^2)
Fengine = 3600N
The answer would most likely be A since obviously gravity weighs things down which helps the every other masses stay settled in place
