I think there's a typo because the answer I'm getting is very large.
This is what I'm getting
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c = speed of light
c = 3.0 x 10^8 m/sec approximately
This is roughly 300 million meters per second
The time it takes the signal to reach the aircraft and come back is 1.4 x 10^3 seconds. Half of this time period is going one direction (say from the radar station to the aircraft), so (1.4 x 10^3)/2 = 7.0 x 10^2 seconds is spent going in this one direction.
distance = rate*time
d = r*t
d = (3.0 x 10^8) * (7.0 x 10^2)
d = (3.0*7.0) x (10^8*10^2)
d = 21.0 x 10^(8+2)
d = 21.0 x 10^10
d = (2.1 x 10^1) * 10^10
d = 2.1 x (10^1*10^10)
d = 2.1 x 10^11 meters
d = 210,000,000,000 meters (this is 210 billion meters; equivalent to roughly 130,487,950 miles)
5lbs is greater.
Hope that helps!
We are given the gravitational potential energy and the height of the ball and is asked in the problem to determine the mass of the ball. the formula to be followed is PE = mgh where g is the gravitational acceleration equal to 9.81 m/s^2. substituting, 58.8 J = m*9.8 m/s^2 * 30 m; m = 0.2 kg.