Advertisements
Advertisements
प्रश्न
The diameter of a wheel is 0.70 m. Find the distance covered by it in 500 revolutions. If the wheel takes 5 minutes to make 500 revolutions; find its speed in :
(i) m/s
(ii) km/hr.
Advertisements
उत्तर
Diameter = 0.70 m
Radius, r = 0.35 m
Distance covered in 1 revolution, i.e. circumference = 2πr = `2 xx 22/7 xx 0.35` = 2.20 m
Distance covered in 500 revolutions = 2.20 x 500 = 1100 m
Time taken = 5 minutes = 5 x 60 = 300 sec.
∴ Speed in m/s = `1100/300`
= `11/3 = 3 2/3` m/s
Again, Distance = 1100 m
= `1100/1000`
= `11/10` km
Time = 5 minutes
= `5/60` hr.
Speed in km/hr = `(11/10)/(5/60) = 11/10 xx 60/5`
= `66/5 = 13.2` km/hr.
Hence 1100 m, (i) `3 2/3` m/s (ii) 13.2 km/hr
APPEARS IN
संबंधित प्रश्न
In the given figure, ΔABC is an equilateral triangle the length of whose side is equal to 10 cm, and ΔDBC is right-angled at D and BD = 8 cm. Find the area of the shaded region. [Take `sqrt(3) = 1.732`.]
An archery target has three regions formed by three concentric circles as shown in figure. If the diameters of the concentric circles are in the ratios 1 : 2 : 3, then find the ratio of the areas of three regions.
In the the following figure, PSR, RTQ and PAQ are three semicircles of diameter 10 cm, 3 cm and 7 cm respectively. Find the perimeter of shaded region.

A wire can be bent in the form of a circle of radius 56 cm. If it is bent in the form fo a square, then its area will be
If the area of a sector of a circle is `5/18` of the area of the circle, then the sector angle is equal to
A pendulum swings through an angle of 30° and describes an arc 8.8 cm in length. Find the length of the pendulum.
The radius of a wheel is 0.25 m. How many revolutions will it make in covering 11 km?
A circular field of radius 105 m has a circular path of uniform width of 5 m along and inside its boundary. Find the area of the path.
Find the area of the biggest circle that can be cut from a rectangular piece 44cm by 28cm. also, find the area of the paper left after cutting out the circle.
A table cover of dimensions 3 m 25 cm × 2 m 30 cm is spread on a table. If 30 cm of the table cover is hanging all around the table, find the area of the table cover which is hanging outside the top of the table. Also find the cost of polishing the table top at ₹ 16 per square metre.
