Answer:
500000000 lbft/s
Explanation:
F = Force or weight = 1000000 lbf
s = Displacement = 10000 ft
t = Time taken = 20 seconds
Work done is given by

Power is given by

One Saucer power is 500000000 lbft/s
Potential energy behind dams
Answer:
Explanation:
When 2 gms of steam condenses to water at 100 degree latent heat of vaporization is releases which is calculated as follows
Heat released = mass x latent heat of vaporization
= 2 x 2260 = 4520 J
When 2 gms of water at 100 degree is cooled to ice water at zero degree heat is releases which is calculated as follows
Heat released = mass x specific heat x( 100-0)
= 2 x 4.2 x 100 = 840 J
When 2 gms of water at zero degree condenses to ice at zero degree latent heat of fusion is releases which is calculated as follows
Heat released = mass x latent heat of fusion
= 2 x 334 = 668 J
When 2 grams of steam at 100 degrees Celsius turns to ice at 0 degrees Celsius heat released will be sum of all the heat released as mentioned above ie
4520 + 840 +668 = 6028 J
The correct answer is:
<span>C) The actual frequency of the siren does not change despite appearances.
In fact, Bob will observe an increase in the apparent frequency as the emergency vehicle approaches him, while Jill will observe a decrease in the apparent frequency as the emergency vehicle moves away from him, because of the Doppler effect (the relative velocity between the observer and the source of the sound is changing), but this effect involves the apparent frequency, while the real frequency of the siren will remain the same.</span>