Answer:
I BELIEVE THE ANSWER A I REMEMBER THAT QUESTION WHEN I DID IT SO THATS THE BEST ONE OUT OF THE 3
Explanation:
A vector would be a quantity that has both magnitude and direction.
Answer:
A) The wave that travels through the rail reaches the microphone first.
B) separation in time between the arrivals of the two pulses is 0.01539 seconds.
Explanation:
Detailed explanation and calculation is shown in the image below
To solve this problem we will apply the concepts related to volume, as a function of length and area, as of mass and density. Later we will take the same concept of resistance and resistivity, equal to the length per unit area. Once obtained from the known constants it will be possible to obtain the area by matching the two equations:
Mass of copper wire
Density
Resistively of copper 
Resistance (R) = 0.390\Omega
Volume is defined as,

(1)
We know that,


(2)
Multiplying equation we have




Therefore the length of the wire is 1.68m
Answer:
option (C)
Explanation:
The amount of heat required to raise the temperature of substance of unit mass by unit degree is called specific heat of that substance.
Its SI unit is Joule / Kg °C.
Every material has a constant value of specific heat.
So, option (c) is correct.