Answer:
C
Explanation:
the formula is a + b = ab
The re<span>sistance of the second wire is 16 R.
where R is the resistance of the first wire.
R = </span>ρ

where l = length of the wire
A = area of the wire
A =

where, r =

Thus, on finding the ratio of resistance of the two wires, we get,

here, R1 = R
l1 = 8m
l2 = 2m
A1=π

A1=π

we get. R2 = 16R
Answer:
Therefore letter <u>C is the correct answer.</u>
Explanation:
In a projectile motion the total time in the air can be calculated using the following equation:
We analyze the y-component motion.

When the final velocity (v(f)) is equal to zero we calculate the upward time and multiplying it by 2 we find the total time in the air. So we will have:


We can see that the <u>total time is directly proportional to the angle</u>, then when <u>θ increase t increase.</u>
Therefore letter C is the correct answer.
I hope it helps you!
Answer:
L = 44,096 m
Explanation:
The speed of the sound wave is constant therefore we can use the relations of uniform kinematics
v = x / t
the speed of the wave in the bar is
v = 15 v or
v = 15 343
v = 5145 m / s
The sound at the bar goes the distance
L = v t
Sound in the air travels the same distance
L = v_air (t + 0.12)
as the two recognize the same dissonance,
v t = v_air (t +0.12)
t (v- v_air) = 0.12 v_air
t = 0.12 v_air / (v -v_air)
l
et's calculate
t = 0.12 343 / (5145 - 343)
t = 8.57 10-3 s
The length of the bar is
L = 5145 8.57 10-3
L = 44,096 m