The answer is B. magnesium I am pretty sure
Potential energy U = mgh
Given h = 123 m,
mg = F = 780 N
Then
U = (123)(780)
= 95940
= 9.59 x 10^4
Answer:
3 fans per 15 A circuit
Explanation:
From the question and the data given, the light load let fan would have been
(60 * 4)/120 = 240/120 = 2 A.
Next, we add the current of the fan motor to it, so,
2 A + 1.8 A = 3.8 A.
Since the devices are continuos duty and the circuit current must be limited to 80%, then the Breaker load max would be
0.8 * 15 A = 12 A.
Now, we can get the number if fans, which will be
12 A/ 3.8 A = 3.16 fans, or approximately, 3 fans per 15 A circuit.
<span>The solution is:
Earth circumference is 2*pi*r=25,130 miles
25,130 miles corresponds to 360Âş, so 5,000 miles corresponds to 360*5000/25130 = 71,6Âş
71,6Âş is equivalent to 71,6*2pi/360=1,25 radians
Angular velocity is 1,25/9=0,139 rad/h</span>
