Find the total surface area of a hollow cylinder of internal radius 3 cm thickness 1 cm and height 14 cm
1320 cm $^{2}$
330 cm $^{3}$
660 cm $^{2}$
990 cm $^{2}$

Question

Find the total surface area of a hollow cylinder of internal radius 3 cm thickness 1 cm and height 14 cm1320 cmdisplaystyle -2-330 cmdisplaystyle -3-660 cmdisplaystyle -2-990 cmdisplaystyle -2-

Toppr Admin · Accepted Answer

Given internal radius r-3 cmExternal radius R-3-1- cm -Since thickness is 1 cm-x2234- Total surface area -2-x3C0-R-r-h-R-x2212-r-2-xD7-227-xD7-4-3-14-4-x2212-3-447-xD7-7-xD7-15-660cm2

Find the total surface area of a hollow cylinder of internal radius 3 cm thickness 1 cm and height 14 cm1320 cm2330 cm3660 cm2990 cm2

Given internal radius r=3 cmExternal radius R=(3+1) cm (Since thickness is 1 cm)∴ Total surface area =2π(R+r)(h+R−r)==2×227×(4+3)(14+4−3)=447×7×15=660cm2

Find the total surface area of a hollow cylinder of internal radius 3 cm thickness 1 cm and height 14 cm
1320 cm $^{2}$
330 cm $^{3}$
660 cm $^{2}$
990 cm $^{2}$

Given internal radius r=3 cm
External radius R=(3+1) cm (Since thickness is 1 cm)
$∴$ Total surface area = $2 π (R + r) (h + R - r)$
= $= 2 \times \frac{22}{7} \times (4 + 3) (14 + 4 - 3) = \frac{44}{7} \times 7 \times 15 = 660 c m^{2}$