Response:
0.9 cm
Clarification:
The following illustrates the calculation of the combined rod's length increase:
As established
Length increase = expansion of aluminum rod + expansion of steel rod

= 0.9 cm
We simply summed the expansions of both the aluminum and steel rods to determine the overall increase in the joined rod's length, which must be factored in
Response:
E = ρ ( R1²) / 2 ∈o R
Clarification:
Provided information
Two cylinders are aligned parallel
Distance = d
Radial distance = R
d < (R2−R1)
To determine
Express the response using the variables ρE, R1, R2, R3, d, R, and constants
Solution
We have two parallel cylinders
therefore, area equals 2
R × l
And we apply Gauss's Law
EA = Q(enclosed) / ∈o......1
Initially, we calculate Q(enclosed) = ρ Volume
Q(enclosed) = ρ (
R1² × l )
Thus, inserting all values into equation 1
produces
EA = Q(enclosed) / ∈o
E(2
R × l) = ρ (
R1² × l ) / ∈o
This simplifies to
E = ρ ( R1²) / 2 ∈o R
The answer is (C) 4 beats per second. The number of beats is computed as the difference between the frequencies of the two tuning forks. Plugging in the frequency values yields a result. Thus, the number of observable beats per second will be 4.