The answer is A- feeling a !etal wire get warmer as you roast a !arshmallow over a fire
Answer:
f = 931.1 Hz
Explanation:
Given,
Mass of the wire, m = 0.325 g
Length of the stretch, L = 57.7 cm = 0.577 m
Tension in the wire, T = 650 N
Frequency for the first harmonic = ?
we know,

μ is the mass per unit length
μ = 0.325 x 10⁻³/ 0.577
μ = 0.563 x 10⁻³ Kg/m
now,

v = 1074.49 m/s
The wire is fixed at both ends. Nodes occur at fixed ends.
For First harmonic when there is a node at each end and the longest possible wavelength will have condition
λ=2 L
λ=2 x 0.577 = 1.154 m
we now,
v = f λ


f = 931.1 Hz
The frequency for first harmonic is equal to f = 931.1 Hz
Force=mass*acceleration
F=ma
20=2.8a
a=20/2.8
a=7.14 m/s^2