Question

Assume that at the surface roughness profile is triangular. If the peak to valley height is 20 μm, the central line average surface roughness ra (in μm) is
a.5
b.6.67
c.10
d.20

Answer 1

Answer:

Radius of circle is 49.9 cm (approx).

Area of circle is 7825.74 cm² (approx).

Explanation:

Given :-

Circumference of circle is 314 cm.

To find :-

Radius of circle.

Area of circle.

Solution :-

Circumference of circle = 2πr

Where,

r is radius of circle.

π is 22/7 or 3.14 .

Put the values :

\rightarrow → 314 = 2πr

\rightarrow → 314 = 2 × 22/7 × r

\rightarrow → 314 = 44/7 × r

\rightarrow → 314 × 7 = 44 × r

\rightarrow → 2198 = 44 × r

\rightarrow → 2198/44 = r

\rightarrow → r = 49.9

Thus,

Radius of circle is 49.9 cm (approx).

Now,

We know,

Area of circle = πr²

Put r in formula :

\rightarrow → 22/7 × (49.9)²

\rightarrow → 22/7 × 2490.01

\rightarrow → 54780.22/7

\rightarrow → 7825.74

Therefore,

Area of circle is 7825.74 cm² (approx).