For this case, the switch is located at point B of the diagram.
Remember that point D is the universal symbol for resistance.
In A what you have is a source of power and in C what you have is a cable.
Therefore, the answer for this case is B.
The strength of the friction doesn't matter. Neither does the distance or the time the asteroid takes to stop. All that matters is that the asteroid has
1/2 (mass) (speed squared)
of kinetic energy when it lands, and zero when it stops.
So
1/2 (mass) (original speed squared)
is the energy it loses to friction in order to come to rest.
Displacement is d
Vf² = Vi² + 2 g d
(-20²) = (+10²) + 2 (-9.8) d
-19.6 d = 300
d = -15.3 m
negative means lower
time is t
d = Vi t + 1/2 g t²
-15.3 = 10 t + (-4.9) t²
4.9 t² - 10 t -15.3 = 0
t = 3.06 s
Hope this helps -John
Answer:
The motion of an object is accelerated when its speed increases.
