Q 3 , 4 and 5 A canal Water is desired A cone of - Maths - Surface Areas and Volumes

Question

Q 3 , 4 and 5 A canal Water is desired
A cone of radius Two parts
Three cubes Three cubes

Kunal Rao · Accepted Answer

Dear Student, Solution for Q3 $Given Length=300cm = 3 m Breadt h = 120 cm = 1 2 m speed = 20 km/hr Time = 20 \min s h=8cm V olume of water coming out of tank=l \times b \times h I n 20km of length of tank=20000m of water is coming out I n one hour,volume of water coming out=3 \times 1 2 \times 20000 = 72000 m^{3} In 20mins ,volu me of water coming out= \frac{72000 \times 20}{60} = 24000 m^{2} Let 'A' be the area irrigated in 20mins A \times \frac{8}{100} = 24000 A= \frac{24000 \times 100}{8} {A=300000m}^{2}$ Solution to Q4 let the height of the cone be h cm radius of the cone be OE= r = 4cm

the cone is divided into two parts cone ABC and frustum BCED OE = 4 cm, AO' = h/2 cm in the triangles AO'C and AOE, ∠AO'C = ∠AOE = 90 deg ∠O'AC = ∠OAE [same angle] ∠ACO' = ∠AEO [since O'C is parallel to OE] therefore the triangles AO'C and AOE are similar triangles therefore the ratio of the corresponding sides are equal AO'/AO = O'C/OE $\frac{h / 2}{h} = \frac{O' C}{O E} O' C = \frac{1}{2} * O E = \frac{1}{2} * 4 O' C = 2 c m$ the radius and height of the cone ABC be 2 cm and h/2 cm therefore the volume of the cone ABC = $\frac{1}{3} π r^{2} * \frac{h}{2} = \frac{1}{3} π * 2^{2} * \frac{h}{2} = \frac{2}{3} π h c m^{3}$ volume of the cone ADE = $\frac{1}{3} π r^{2} h = \frac{1}{3} π * 4^{2} h = \frac{16}{3} π h c m^{3}$ the volume of the frustum = volume of the cone ADE - volume of the cone ABC $= \frac{16}{3} π h - \frac{2}{3} π h = \frac{14}{3} π h c m^{3}$ ratio of the volume of the two parts = volume of the cone ABC : volume of the frustum $= \frac{2}{3} π h : \frac{14}{3} π h = 1 : 7$ hope this helps you Kindly ask the remaining queries in a separate thread Regards

Q. 3 , 4 and 5 . A canal... Water is desired A cone of radius..... Two parts Three cubes .... Three cubes

Q. 3 , 4 and 5 . A canal... Water is desired
A cone of radius..... Two parts
Three cubes .... Three cubes