Question

# A ladder is $$2$$m long has lower end on the ground and the other end in contact with a vertical wall. The lower end slips along the ground. If upper end is moving downward at the rate of $$25$$ cm/sec and when upper end of ladder is $$1$$m above the ground, then the rate at which lower end of the ladder is sliding on the ground is?

A
253
B
223
C
223
D
253

Solution

## The correct option is C $$-\dfrac{25}{\sqrt{3}}$$$$x^2+y^2=4\Rightarrow 2x\dfrac{dx}{dt}+2y\dfrac{dy}{dt}=0\Rightarrow \dfrac{dx}{dt}=-\dfrac{y}{x}\cdot \dfrac{dy}{dt}$$When upper end is $$1$$m above the ground, $$\dfrac{dx}{dt}=-\dfrac{1}{\sqrt{3}}\cdot 25=-\dfrac{25}{\sqrt{3}}$$ cm/sec.Mathematics

Suggest Corrections

0

Similar questions
View More

People also searched for
View More