I’m pretty sure it would be sound waves! :)
Only ' A ' is always true.<em> (choice-1)</em>
' B ' is not true when you drop a red hot spoon into cold soup.
' C ' is not true when you drop a red hot marble into a cool swimming pool.
a) We use the formula:
T = [g sinθ – a] * m
where g is gravity, θ is the angle, a is acceleration, m is mass
T = [9.81 sin37 - 2.00] * 12 = 46.85 N <span>
b) We use the formula for moment of interia:</span>
I = T * r² / a
I = 46.85 * 0.10² / 2.00 = .2343 kg∙m² <span>
c) The formula we can use here is:</span>
w = α * t = (a/r) * t
w = (2/.10) * 2
<span>w = 40 rad/sec</span>
I think the correct answer would be to electrolyze water (run an electric current through it) to decompose it into hydrogen and oxygen. Assuming 100% efficiency, it is said that it needs about 40kWh per kilogram of water to fully decompose it.
Missing part in the exercise. Complete text:
"A hair dryer draws 14.5 A when plugged into a 120-V line. Assume direct current.
(a) What is its resistance? Express your answer to two significant figures and include the appropriate units."
(b) How much charge passes through it in 11 min ? Express your answer to two significant figures and include the appropriate units.
Solution
(a) We can calculate the resistance by using Ohm's law:

Since we know that
and
, we can find R:

(b) The current is equal to the quantity of charge by unit of time:

In our problem, t=11min=660 s, so we can calculate the charge passed through the hair dryer:
