Density is a physical property that describes the relationship between mass and volume. Density is the amount of matter in a given space, or volume.
Answer:
The Spanish philosopher George Santayana wrote, “those who cannot remember the past are condemned to repeat it.” When it comes to climate change, repeating the past is a luxury we can’t afford. If partisan politics continues to derail policy or if denial continues to win over science, it will mean irreversible changes to our planet. Future generations will look at ours as the one that didn’t have the courage to act, rather than the one that recognized the fierce urgency of the moment and met it head on.
With this in mind, we’ve created a climate change timeline highlighting the evolution of science, the intrusion of denial, and the sluggishness of policy over the past 200 years. Let’s learn from the mistakes of the past, so we can make tomorrow a brighter—but not hotter—future.
Answer:
dβ = 70. 77 dβ
Explanation:
The intensity of sound in decibels is
dβ = 10 log I/I₀
let's look for the intensity of this signal
I / I₀ = 10 dβ/10
I / I₀ = 3.981 10⁶
the threshold intensity of sound for humans is I₀ = 1 10⁻¹² W / m²
I = 3.981 10 ⁶ 1 10⁻¹²
I = 3,981 10⁻⁶ W / m²
It is indicated that 3 cornets are placed in the circle, for which total intensity is
I_total - 3 I
I_total = 3 3,981 10⁻⁶
I_total = 11,943 10⁻⁶ W / m²
let's reduce to decibels
dβ = 10 log (11,943 10⁻⁶/1 10⁻¹²)
dβ = 10 7.077
dβ = 70. 77 dβ
A : lighter than lead shot, reducing its velocity and distance
Initial momentum = 0.15 kg * (-5 m/s) = - 0.75 N*s
final momentum = 0.15 * ( 3 m/s) = 0.45 N*s
Change in momentum = final momentum - initial momentun =
= 0.45N*s - (- 0.75N*s) = 1.2 N*s
Answer: 1.2 N*s
