Physics - Kinematics Question with Solution | TestHub

Person's speed walking only is $\frac{1}{60}\frac{\text{ "escalator" }}{\text{ second }}$ Standing the escalator without walking the speed is $\frac{1}{40}\frac{\text{ "escalator" }}{\text{ second }}$ Walking with the escalator going, the speed add. So, the person's speed is $\frac{1}{60}+\frac{1}{40}=\frac{15}{120}$ $\frac{\text{ "escalator" }}{\text{ second }}$ So, the time to go up the escalator ("seconds per escalator") is $$t=\frac{120}{5}=24\text{ second }$$