Advertisements
Advertisements
प्रश्न
A bicycle wheel, diameter 56 cm, is making 45 revolutions in every 10 seconds. At what speed in kilometre per hour is the bicycle traveling?
Advertisements
उत्तर
Diameter = 56 cm
∴ Radius, r = 28 cm
∴ Distance travelled in 1 revolution
i.e. circumference = `2pir = 2 xx 22/7 xx 28 = 176` cm
∴ Distance travelled in 45 revolution
= `176 xx 45 = 7920 "cm" = 7920/(100 xx 1000)`km
Time = 10 sec = `10/(60 xx 60)` hr.
Speed = `(7920/(100 xx 1000))/(10/(60 xx 60))`m
= `7920/(100 xx 1000) xx (60 xx 60)/10 = 28512/1000` km/hr
= 28.512 km/hr
APPEARS IN
संबंधित प्रश्न
The area of a square filed is 8 hectares. How long would a man take to cross it diagonally by walking at the rate of 4 km per hour?
Find the area of the circle in which a square of area 64 cm2 is inscribed. [Use π = 3.14]
In the given figure, the side of square is 28 cm and radius of each circle is half of the length of the side of the square where O and O' are centres of the circles. Find the area of shaded region.
If a square is inscribed in a circle, what is the ratio of the areas of the circle and the square?
Find the area of the largest triangle that can be inscribed in a semi-circle of radius runits.
In the given figure, OABC is a quadrant of a circle of radius 3.5 cm with centre O. If OD = 2 cm, find the area of the shaded portion.
In the given figure, ∆ABC is right-angled at A. Semicircles are drawn on AB, AC and BC as diameters. It is given that AB = 3 cm and AC = 4 cm. Find the area of the shaded region.
A roller has a diameter of 1.4 m. Find :
(i) its circumference ;
(ii) the number of revolutions it makes while travelling 61.6 m.
A sprinkler placed at the centre of a flower garden sprays water covering a circular area. If the area watered is 1386 cm2, find its radius and diameter
A table top is semicircular in shape with diameter 2.8 m. Area of this table top is ______.
