l=√(3.5)^2+(3.25)^2 solve it with step by step
Answers
Answer:
Rasheed got a playing top as his birthday present, which surprisingly had no colour on it. He wanted to colour it with his crayons. The top is shaped like a cone surmounted by a hemisphere .the entire top is 5cm in height and the diameter is 3.5cm
Step-by-step explanation:
Diameter of hemisphere = 3.5 cm
So radius of hemispherical portion of the lattu = r = 3.52cm3.52cm = 1.75
r = Radius of the concial portion = 3.523.52 = 1.75
Height of the conical portion = height of top - radius of hemisphere = 5 - 1.75 = 3.25 cm
Let I be the slant height of the conical part. Then,
l2=h2+r2l2=h2+r2
l2=(3.25)2+(1.75)2⇒l2=10.5625+3.0625⇒l2=13.625⇒l=13.625−−−−−√⇒l=3.69l2=(3.25)2+(1.75)2⇒l2=10.5625+3.0625⇒l2=13.625⇒l=13.625⇒l=3.69
Let S be the total surface area of the top. Then,
S=2πr2+πrlS=2πr2+πrl
⇒S=πr(2r+l)⇒S=πr(2r+l)
⇒S=227×1.75(2×1.75+3.7)=5.5(3.5+3.7)=5.5(7.2)=39.6cm2
