Asked by Cryztal Celeste on Sep 23, 2024

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A free-falling object is described by h=35t+12at2h = 35 t + \frac { 1 } { 2 } a t ^ { 2 }h=35t+21at2 , where h is the height above the ground, t is the amount of time the object is falling, and a is the acceleration. Solve the equation for a .

A) a=2(h−35t) ta = \frac { 2 ( h - 35 t ) } { t }a=t2(h35t)
B) a=2(h+35t) t2a = \frac { 2 ( h + 35 t ) } { t ^ { 2 } }a=t22(h+35t)
C) a=2(h−35t) t2a = \frac { 2 ( h - 35 t ) } { t ^ { 2 } }a=t22(h35t)
D) a=h−35tt2a = \frac { h - 35 t } { t ^ { 2 } }a=t2h35t
E) a=h−35t2t2a = \frac { h - 35 t } { 2 t ^ { 2 } }a=2t2h35t

Free-Falling Object

An object that is falling under the sole influence of gravity, with no forces like air resistance acting upon it.

Acceleration

The rate of change of velocity of an object with respect to time.

  • Understand and manipulate formulas to isolate a variable.
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Verified Answer

QE
Qasem Elsharqawiabout 6 hours ago
Final Answer :
C
Explanation :
Firstly, taking the derivative of h with respect to t gives the velocity, v:

v=dhdt=35+atv = \frac{dh}{dt} = 35+atv=dtdh=35+at

Then, taking the derivative of v with respect to t gives the acceleration, a:

a=dvdt=ddt(35+at)=ddt(35)+ddt(at)=0+a=aa = \frac{dv}{dt} = \frac{d}{dt}(35+at) = \frac{d}{dt}(35) + \frac{d}{dt}(at) = 0 + a = aa=dtdv=dtd(35+at)=dtd(35)+dtd(at)=0+a=a

Therefore, the acceleration is just the coefficient of t in the equation for h:

a=2(h−35t)t2a = \frac{2(h-35t)}{t^2}a=t22(h35t)

which is choice C.