Answer:
Explanation:
Remark
The only thing that might trip you up is what to do with the angle. The vertical component of the 15 degrees does no work against anything. So the 15 degrees limits the horizontal force.
The formula is
Work = F * d * cos(15)
The givens are
F = 2000 N
d = 30 m
Cos(15) = 0.9659
Solution
Work = 2000 * 30 * cos(15)
Work = 57,955
Rounded to two places would be 5.8 * 10^4
C
Answer:
A. I = V / R = 12 / 252 = .048 amps
V = I * R = .048 * 252 = 12 V
V is also the reading the voltage across the battery (12 Volts)
You haven't told us the "wattage" rating of the bulb. We'll just have to call it ' W ' .
The bulb uses energy at the rate of W watts, or 0.001W kilowatts.
In 12 hours, it uses <em>0.012W kilowatt-hours </em>of energy.
= = = = =
W watts = W Joules/second
1 hour = 3600 seconds
12 hours = (12 x 3600) seconds
Energy = (W Joule/sec) x (12 x 3600 sec)
<em>Energy = 43,200W Joules</em>
Answer:
0.2s
Explanation:
SO for the dolphin to hear its echo, the sound wave must travel a distance twice as much as the displacement between the dolphin and the ocean floor. So d = 154 * 2 = 308 m
Since the speed of sound in ocean floor is v = 1533m/s we can find out the time by dividing the distance d by the speed of sound
t = d / v = 308 / 1533 = 0.2s
