ABC26GN4574 · Area
Subject: General Aptitude · Chapter: Area · Exam: 2008 · Marks: · Difficulty:
The radius of the wheel of a vehicle is 70 cm. The wheel makes 10 revolutions in 5 seconds. The speed of the vehicle is
(a)29.46 km/hr
(b)31.68 km/hr
(c)32.72 km/hr
(d)36.25 km/hr
Answer
Explanation
Distance covered in $5 \mathrm{sec}=\left(2 \times \frac{22}{7} \times 70 \times 10\right) \mathrm{cm}$ $$=4400 \mathrm{cm}=44 \mathrm{m} .$$ Distance covered in $1 \mathrm{sec}=\left(\frac{44}{5}\right) \mathrm{m}=8.8 \mathrm{m}$. $$\begin{aligned} \therefore \text { Speed } & =8.8 \mathrm{m} / \mathrm{sec}=\left(8.8 \times \frac{18}{5}\right) \mathrm{km} / \mathrm{hr} \\ & =31.68 \mathrm{km} / \mathrm{hr} \end{aligned}$$
Open in whiteboard · Browse this chapter in the app