Answer: 9496200 joules
Explanation:
Gravitational potential energy, GPE is the energy possessed by the moving plane since it moves against gravity.
Thus, GPE = Mass m x Acceleration due to gravity g x Height h
Since Mass = 1900kg
g = 9.8m/s^2
h = 510 metres (units of height is metres)
Thus, GPE = 1900kg x 9.8m/s^2 x 510m
GPE = 9496200 joules
Thus, the gravitational potential energy of the airplane is 9496200 joules
Answer:
61.85 ohm
Explanation:
L = 12 m H = 12 x 10^-3 H, C = 15 x 10^-6 F, Vrms = 110 V, R = 45 ohm
Let ω0 be the resonant frequency.


ω0 = 2357 rad/s
ω = 2 x 2357 = 4714 rad/s
XL = ω L = 4714 x 12 x 10^-3 = 56.57 ohm
Xc = 1 / ω C = 1 / (4714 x 15 x 10^-6) = 14.14 ohm
Impedance, Z = 
Z = \sqrt{45^{2}+\left ( 56.57-14.14 )^{2}} = 61.85 ohm
Thus, the impedance at double the resonant frequency is 61.85 ohm.
Work = (force) x (distance)
62,500 joules = (boulder's weight) x (25 meters)
Divide each side by (25 meters) :
Boulder's weight = (62,500 joules) / (25 meters) = <u>2,500 newtons</u>
That's about 562 pounds.