Advertisements
Advertisements
Question
An express train is running between two stations with a uniform speed. If the diameter of each wheel of the train is 42 cm and each wheel makes 1200 revolutions per minute, find the speed of the train.
Advertisements
Solution
radius of the wheel = `42/2` = 21 cm
Circumference of the wheel = 2π x 21 = 132 cm
Distance travelled in one minute
= 132 x 1200
= 158400 cm
= 1.584 km
Hence the speed of the train
= `[1.584 "km"]/[1/60"hr"]`
= 95.04 km/hr.
APPEARS IN
RELATED QUESTIONS
The minute hand of a clock is 10cm long. Find the area of the face of the clock described by the minute hand between 9 A.M. and 9.35 A.M.
Shazli took a wire of length 44 cm and bent it into the shape of a circle. Find the radius of that circle. Also find its area. If the same wire is bent into the shape of a square, what will be the length of each of its sides? Which figure encloses more area, the circle or the square? (Take `pi = 22/7`)
Find the angle subtended at the centre of circle of radius 5cm by an arc of length `((5pi)/3)` cm
Below fig shows a sector of a circle, centre O. containing an angle ЁЭЬГ°. Prove that
Area of shaded region is`r^2/2(tantheta −(pitheta)/180)`
The radius of a sector of a circle is 7 cm. If the measure of the arc of the sector is 210°, find the area of the sector in case.
A sector of 56°, cut out from a circle, contains 17.6 cm2. Find the radius of the circle.
A 4.2 m wide road surrounds a circular plot whose circumference is 176 m. Find the cost of paving the road at Rs 75 m 2.
Find the total surface area and volume of a hemisphere whose radius is 10 cm.
Draw the circumcircle of Δ PMT in which PM = 5.4, P = 60°, M = 70°.
