Advertisements
Advertisements
प्रश्न
A cart wheel makes 9 revolutions per second. If the diameter of the wheel is 42cm, find its speed in km per hour. (Answer correct to the nearest km)
Advertisements
उत्तर
The Circumference of a Circle with diameter d is πd
The Circumference of a Circle with diameter 42cm is π x 42
= `(22)/(7) xx 42`
= 22 x 6
= 132cm
⇒ distance moved in 1 revolution = 132cm
Total distance moved in 9 revolutions
= 9 x 132cm
= 1188cm
Total distance moved in 1 second = 1188cm
⇒ Total distance moved in 1 hour
= 1188cm x 60 x 60
= 4276800cm
= `(4276800)/(100 xx 1000)"km"`
⇒ Speed = 42.7km/hr.
∴ Speed = 42.7km/hr.
APPEARS IN
संबंधित प्रश्न
In the given figure,
\[\square\] PQRS is a rectangle. If PQ = 14 cm, QR = 21 cm, find the areas of the parts x, y, and z.
Find the perimeter of the shaded region in the figure, if ABCD is a square of side 14 cm and APB and CPD are semicircles.
The circumference of a given circular park is 55 m. It is surrounded by a path of uniform width of 3.5 m. Find the area of the path.
The diameter of a circle is 5.6 cm. Find its circumference.
Find the area and perimeter of the following semicircles: Radius = 1.4cm
Find the area and perimeter of the following semicircles: Diameter = 5.6cm
A wire in the form of a circle of radius 42cm. It is bent into a square. Determine the side of the square and compare the area of the regions enclosed in the two cases.
What is the circumference of a circle of diameter 10 cm (Take π = 3.14)?
Formula used to find the circumference of a circle is
The circumferences of two circles are in the ratio 4 : 5. What is the ratio of their radii?
