<span>c. They help discard some myths about objects in space.
When we learn something new, then we know more stuff,
and that helps us avoid ignorance and superstition.
The REAL question is:
</span><span>Why should we continue to send robotic spacecrafts,
and NOT spacecrafts piloted by people ?</span>
Answer:
51.2 J, 86.2 J, 137.4 J
Explanation:
The kinetic energy of the ball is given by:

where
m = 0.40 kg is its mass
v = 16 m/s is its speed
Substituting,

The potential energy of the ball is given by

where
m = 0.40 kg
is the acceleration of gravity
h = 22 m is the heigth of the cliff
Substituting,

Finally, the total mechanical energy is the sum of the kinetic energy and the potential energy:

Answer:
Explanation:
b) Gravity reduces the initial upward velocity to zero in a time of
t = v/g = 40/10 = 4 s
a) h = v₀t + ½gt² = 40(4) + ½(-10)4² = 80 m
or
v² = u² + 2as
h = (0² - 40²) / 2(-10) = 80 m
V = 340 m/s
f = 256 Hz
lambda (wavelength)
v = f*lambda
340 = 256 * lambda
340/256 = lambda
lambda = 1.328 m