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
Find the length of the diagonal of a square whose area is `128 cm^2` Also, find its perimeter.
A square of diagonal 8 cm is inscribed in a circle. Find the area of the region lying outside the circle and inside the square.
In the following figure, an equilateral triangle ABC of side 6 cm has been inscribed in a circle. Find the area of the shaded region. (Take π = 3.14).

In the given figure, ABCD is a trapezium with AB || DC, AB = 18 cm DC = 32 cm and the distance between AB and DC is 14 cm. Circles of equal radii 7 cm with centres A, B, C and D have been drawn. Then find the area of the shaded region.
(Use \[\pi = \frac{22}{7}\]

In a hospital used water is collected in a cylindrical tank of diameter 2 m and height 5 m. After recycling, this water is used to irrigate a park of hospital whose length is 25 m and breadth is 20 m. If tank is filled completely then what will be the height of standing water used for irrigating the park.
ABCD is a square of side 4 cm. If E is a point in the interior of the square such that ΔCEDis equilateral, then area of Δ ACE is
The area of the sector of angle θ° of a circle with radius R is
Find the area of a flat circular ring formed by two concentric circles (circles with the same centre) whose radii are 9 cm and 5 cm.
Diameter of a circular garden is 9.8 m. Find its area.
What is the diameter of a circle whose area is equal to the sum of the areas of two circles of radii 40cm and 9cm?
