A 20-ft ladder rests against a vertical wall

MATHEMATICS · Single correct · AP · Calculus AB · Contextual Applications of Differentiation · Contextual Applications of Differentiation

Problem

A 20-ft ladder rests against a vertical wall. Beginning at time t=0t=0 s, the foot of the ladder is pulled horizontally away from the wall so that its horizontal velocity is v(t)=0.4t ft/sv(t)=0.4t\text{ ft/s}. At t=5 st=5\text{ s} the foot is 12 ft from the wall. What is the instantaneous vertical acceleration of the top of the ladder at t=5 st=5\text{ s}? (a) −0.55 ft/s2-0.55\text{ ft/s}^2 (b) +0.69 ft/s2+0.69\text{ ft/s}^2 (c) −0.69 ft/s2-0.69\text{ ft/s}^2 (d) −0.31 ft/s2-0.31\text{ ft/s}^2

Related theory

Browse the problem library