Answer:
The atomic nucleus is the small, dense region consisting of protons and [[]]s at the center of an atom
Explanation:
The full question is:
On a keyboard, you strike middle C, whose frequency is 256 Hz. What is the period of one vibration of this tone?
The period of a vibration is the time it takes for the particle to make one full oscillation. Frequency is by definition number of full oscillations per unit of time.
When the frequency is expressed in Hz that unit of time is one second.
So there is the following relation between frequency and period:

When we plug in the numbers we get:
Answer:
The length of the wire is 83.2 m.
Explanation:
Given that,
Power of heater, P = 300 W
Voltage, V = 110 V
The resistivity of nichrome wire is, 
The electric power of a wire is given by :

Area of cross section of the wire is :

Resistance of a material is given by :

So, the length of the wire is 83.2 m. Hence, this is the required solution.
Answer:
the signs of heat and work are; -Q and -W
Explanation:
The first law of thermodynamics is given by; ΔU = Q − W
where;
ΔU is the change in internal energy of a system,
Q is the net heat transfer (the sum of all heat transfer into and out of the system)
W is the net work done (the sum of all work done on or by the system).
Now, The system in this case is the tire and since the air gets warmer, heat must have left the system. Therefore Q is negative (-Q).
Since work is done by the system, W remains negative.
Thus, the signs of heat and work are; -Q and - W
Answer:Compared to other pathogens, such as bacteria, viruses are minuscule. And because they have none of the hallmarks of living things — a metabolism or the ability to reproduce on their own, for example — they are harder to target with drugs.
Explanation: