1.) temperature change, 2.) color change, 3.) gas formation
Answer: D Although the total energy remains constant, nonrenewable fuels convert chemical energy into forms that are difficult or impossible to use again.
Explanation:
The first law of thermodynamics says that energy can neither be created nor destroyed; energy can only be transferred or changed from one form to another.
Answer:
a) 12.8 N
b) 3.2 m/s²
Explanation:
I'm guessing the period is 0.5π s.
Period of a spring in simple harmonic motion is:
T = 2π √(m/k)
Given T = 0.5π and m = 2 kg:
0.5π = 2π √(2/k)
0.25 = √(2/k)
0.0625 = 2/k
k = 32
The spring constant is 32 N/m, and the maximum displacement is 0.4 m. The maximum force can be found with Hooke's law:
F = kx
F = (32 N/m) (0.4 m)
F = 12.8 N
The acceleration can be found with Newton's second law:
∑F = ma
kx = ma
(32 N/m) (0.2 m) = (2 kg) a
a = 3.2 m/s²
The pitch of the sound of the car will appear to be <span>lower than the pitch of the car next to you</span>
The intensity of the sound wave is defined as the ratio between the power of the wave and the area through which the wave passes:

where
I is the intensity
P is the power
A is the area
If we use the data of the problem,

and

, we find the intensity of the sound wave: