Heat used by electric heater :
Q = m • c • ∆T
Q = (75 kg)(4200 J/kg°C)(43°C - 15°C)
Q = 8.82 × 10⁶ J
Cost of electrical energy :
Cost = (8.82 × 10⁶ J)/(3.6 × 10⁶ J) • ($ 0.15)
Cost = $ 0.3675
Answer:
117.8 m/s
Explanation:
Given that:
String length, L = 0.28
pipe length, L' = 0.82
Speed of sound in air, v = 345 m/s
n = 3 (3rd harmonic)
Frequency, f of 3rd harmonic ;
f = (v*n) / 2L - - - - (1)
for the pipe: ; 3rd harmonic
f = (v*n) / 2L' - - - (2)
Equating (1) and (2)
(v*n) / 2L = (v*n) / 2L'
2L' * v * n = v* n * 2L
v = vL / L'
v = (345 * 0.28) / 0.82
v = 96.6 / 0.82
v = 117.80487
v = 117.8 m/s
Explanation:
Both graphs show plotted points forming a curved line. Curved lines have changing slope; they may start with a very small slope and begin curving sharply (either upwards or downwards) towards a large slope. In either case, the curved line of changing slope is a sign of accelerated motion (i.e., changing velocity).