Hi!!
We have to use the formulas for uniform accelerated motion with an
acceleration of 3.71 m/s^2 .Remember that the free fall is an special
case of this kind of motion, a free-falling object is an object which
is falling under the sole influence of gravity. So under free fall all
objects have the same constant acceleration, the gravity acceleration.
These kinematics equations can be used when an object's linear
acceleration is uniform (constant):
s, v0, a and t -----> s = v0*t + 1/2*a*t^2
vf, v0, a and s -----> vf^2 = v0^2 + 2*a*s
vf, v0, a and t -----> vf = v0 + a*t
s, v0, vf and t -----> s = 1/2*(v0 + vf )*t
The metric units of measurement for these quantities are:
s in meters
v in m/sec
t in sec
a in m /sec^2
What would a rock's velocity be 3s after you dropped it on Mars?
We will use:
vf, v0, a and t -----> vf = v0 + a*t
where a = 3.71 m/s^2; v0 = 0 m/s ; t = 3s and vf is unknown.
vf = v0 + a*t =
= 0 m/s + 3.71 m/s^2 * 3s =
= 11.13 m/s
A rock's velocity 3s after you dropped it on Mars will be 11.13 m/s.
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How far would a rock fall in 3s if you dropped it on Mars?
We will use:
s, v0, a and t -----> s = v0*t + 1/2*a*t^2
where s is unknown; v0 = 0 m/s; a = 3.71 m/s^2 and t = 3s.
s = v0*t + 1/2*a*t^2 =
= 0 m/s * 3 s + 1/2 * 3.71 m/s^2 * 9 s^2 =
= 16.695 m
A rock will fall 16.695 m in 3s if you dropped it on Mars (from an
altitude higher than 16.695 m).
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For references see:
"Free fall motion":
http://theory.uwinnipeg.ca/mod_tech/node17.html
"Kinematic Equations and Free Fall":
http://www.glenbrook.k12.il.us/gbssci/phys/Class/1DKin/U1L6c.html
"Uniformly Accelerated Motion":
http://online.cctt.org/physicslab/content/Phy1/lessonnotes/acceleratedmotion/lessonacceleration.asp
I hope that this helps you. feel fre to request for a clarification if you need it.
Regards.
livioflores-ga |
