<span>Radiant energy travels in straight lines until it strikes an object where it can be absorbed, reflected or transmitted</span>
Answer:
b = 5.164 m is the minimum thickness of the dam
Explanation:
Given
SG = 5
h = 20 m
b = ?
w = 1 m
γw = 9800 N/m³
We can get the forces as follows
Fp = γw*(h/2)*(h*w)
⇒ Fp = (9800 N/m³)*(20 m/2)*(20 m*1 m) = 1.96*10⁶N
W = (SG*γw)*(h*b*w)
⇒ W = (5*9800 N/m³)*(20 m*b*1 m) = (9.8*10⁵N/m)*b
Then, we apply
∑M₀ = 0 (counterclockwise)
- Fp*(h/3) + W*(b/2) = 0
⇒ - 1.96*10⁶N*(20 m/3) + (9.8*10⁵N/m)*b*(b/2) = 0
- 13.066*10⁶N-m + (4.9*10⁵N/m)*b² = 0
⇒ b = 5.164 m is the minimum thickness of the dam
D. A magnetic field created by the electric current causes the compass needle to move.
The primary source would be the original article published in a scientific journal. All other choices would be based on information from the original article.
Newspapers would only pick up the information from the journal itself, or from the authors. Books follow after the original article, after it has gained momentum among the research community. The public lecture at a museum would be based on work from the journal article.
