Answer: The fundamental frequency of the slinky = 8Hz
An input frequency of 28 Hz will not create a standing wave
Explanation:
Let Fo = fundamental frequency
At third harmonic,
F = 3Fo
If F = 24Hz
24 = 3Fo
Fo = 24/3 = 8Hz
If an input frequency = 28 Hz at 3rd harmonic
Let find the fundamental frequency
28 = 3Fo
Fo = 28/3
Fo = 9.33333Hz
Since Fo isn't a whole number, it can't create a standing wave
Answer:
Yes the body will receive a dangerous shock in both cases.
Explanation:
Different parts of the body has different resistance. skin has the high resistance as compared to other organs of the body.
Dry skin has high resistance than wet skin this is because water is relatively good conductor of electricity, it adds parallel path to the current flow and hence reduces skin resistance.
Dry hands body has approximately 500 kΩ resistance and if 120 V electricity supply current received will be:
I = V/R= 120/ 500*10^3
I= 0.24 mA
Even the current seems is much lower than the safe zone but this is the case in case of DC voltage in case of AC voltage the body will receive a shock this is because the skin pass more current when the voltage is changing i.e. AC.
Similarly for wet hands body resistance is 1 kΩ. so the current through the body seems to be:
I = 120 / 1000
I = 12 mA
The current is higher than safe zone so the body will receive a dangerous shock.
Answer:
W = 3/2 n (T₁- T₂)
Explanation:
Let's use the first law of thermodynamics
ΔE = Q + W
in this case the cylinder is insulated, so there is no heat transfer
ΔE = W
internal energy can be related to the change in temperature
ΔE = 3/2 n K ΔT
we substitute
3/2 n (T₂-T₁) = W
as the work is on the gas it is negative
W = 3/2 n (T₁- T₂)
He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect.
