Question
A rectangular piece of copper foil of length 49 cm and
area 1078 cm2 is folded along its width to form a cylinder such that there is only one layer of copper foil on any part of the cylinder. What is the volume (in cm3) of the cylinder so formed?Solution
Width of the rectangular piece of copper foil = 1078/49 = 22 cm Since the foil is folded along its width to form a cylinder without any double layer, circumference of the cylinder formed = width of the rectangular foil Also, height of the cylinder so formed = length of the rectangular copper foil So, 2 × π × radius = 22 Radius of cylinder = 22 ÷ (2 × 22/7) = (22/44) × 7 = 3.5 cm So, volume of the cylinder so formed = π × (radius)2 × height = (22/7) × 3.5 × 3.5 × 49 = 1886.5 cm³
If I is the incentre of ΔABC , if ∠BIC = 1300  , then what is the measure of ∠BAC?
In the given figure, PQR is a triangle and quadrilateral ABCD is inscribed in it. QD = 2 cm, QC = 5 cm, CR = 3 cm. BR = 4 cm. PB = 6 cm. PA = 5 cm and A...
What will be circumradius of a right angle triangle whose base is 20cm & height is 21cm ?
In ΔABC, PQ is parallel to BC If AP: PB= 3:4 and AQ= 6 cm, AC is equal to?
The sides of a triangle are 24 cm, 26 cm and 10 cm. At each of its vertices, circles of radius 4.2 cm are drawn. What is the area (in cm²) of the t...
Triangle ABC is similar to triangle PQR and AB : PQ = 2 : 3. AD is the median to the side BC in triangle ABC and PS is the median to the side QR in tria...
Let A, B, and C be the mid-points of sides PQ, and QR PR, respectively, of ΔPQR. If the area of ΔPQR is 64cm², then find the area of ΔABC.
...If G is the centroid and AD, BE, CF are three medians of ∆ABC with area 42 cm 2 , then the area of ∆BGD is?
If in a right angle triangle ABC, Angle B is a right angle. AB = 8 cm, BC= 15cm if BD is perpendicular to AC find the length of BD?Â
In triangle ABC, AB = AC. Point D lies on AB such that AD = DC = BC. Find the value of ∠BDC.