Answer:
Explanation:
First of all, we can find the speed of the sound wave, which is given by:
where
f = 645 Hz is the frequency
is the wavelength
Substituting,
Now we can find the temperature of the air by using the following relationship:
where T is the temperature in Celsius degrees. Since we know v = 322.5 m/s, we can re-arrange the formula to find the temperature:
Answer:
B. positive; negative.
Explanation:
From the viewpoint of Principle of Energy Conservation and Work-Energy Theorem, we notice that gravity represents a conservative force, associated with gravitational potential energy, whereas air resistance is a non-conservative force, associated with dissipated work. Therefore, the work done by gravity is positive and work done by air resistance is negative. Therefore, the correct answer is B.
The answer is (B. The study of Matter and Energy) but technically you could consider physics all of these as engineering is based on physics and that would be the study of inventions, chemistry and biology were both discovered because of physics, and physics invokes more math than any other subject as it applies math to the entire Universe.
Answer:
Explanation:
From frequency of oscillation
Initially with the suspended string, the above equation is correct for the relation, hence
where k is force constant and m is the mass
When the spring is cut into half, by physics, the force constant will be doubled as they are inversely proportional
Employing f2/ f1, we have
You oughtta be able to do this one.
The "efficiency" is just the portion of the input work that
comes out in a useful form.
If the efficiency is 70%, that tells you that however much work
you put INto the machine, the machine will do 70% of that much
work for you at the output side.
Put 20,000 J in ... out comes (0.70) x (20,000 J) = 14,000 J .
What happens to the other 30% of the work you put into it ?
It turns into HEAT. That's why machines always have to be
cooled somehow while they're running.
