Question

How long is the arc intercepted by central angle of pi over 2 rad in a circle with radius of 4.5 cm round your answer to the nearest 10th use 3.14 for pie

Answer 1

Explanation:

The formula for determining the length of an arc is expressed as

Length of arc = θ/360 × 2πr

Where

θ represents the central angle.

r represents the radius of the circle.

π is a constant whose value is 3.14

From the information given,

Radius, r = 4.5 cm

180 degrees = π radians

1 radian = 180/π

2 radians = 2 × 180/π = 360/π degrees

Therefore,

Length of arc = (360/π) /360 × 2 × π × 4.5

Length of arc = 9 cm

Answer 2

L = 7.1 cm (to the nearest 10th)

Length of an arc equals 7.1 cm

Explanation:

Given;

Central angle of arc = π/2 rad

Radius = 4.5 cm

π = 3.14

Length of an arc L = (θ/360) × 2πr (angle in degrees)

for radian.

L = θr

Substituting the values;

L = π/2 × r = 3.14/2 × 4.5 = 7.065 cm

L = 7.1 cm (to the nearest 10th)