Question

A body is moving according to the equation $x = at + bt^{2} - ct^{3}$ where $x =$ displacement and $a,\mspace{6mu} b$ and $c$ are constants. The acceleration of the body is

• A. $a + 2bt$
• B. $2b + 6ct$
• C. $2b - 6ct$
• D. $3b - 6ct^{2}$

Answer 1

Answer: (C)

$2b - 6ct$

Answer 2

$x = at + bt^{2} - ct^{3},\mspace{6mu} a = \frac{d^{2}x}{dt^{2}} = 2b - 6ct$