Question

7. The length of a minute hand of a clock is 3.5cm. Find the angle it turns through if it

Answer 1

Answer:

The angle it turns through if it  sweeps an area of 48 cm²   is   448.8°

Step-by-step explanation:

If the length of a minute hand of a clock is 3.5cm, to find the angle it turns through if it  sweeps an area of 48 cm, we will follow the steps below;

area of a sector = Ф/360  ×   πr²

where Ф is the angle,  r is the radius   π is a constant

from the question given, the length of the minute hand is 3.5 cm, this implies that radius r = 3.5

Ф =?   area  of the sector= 48 cm²    π = $\frac{22}{7}$

we can now go ahead to substitute the values into the formula  and solve Ф

area of a sector = Ф/360  ×   πr²

48   =  Ф/360  ×  $\frac{22}{7}$ × (3.5)²

48 = Ф/360  ×  $\frac{22}{7}$ ×12.25

48 = 269.5Ф / 2520

multiply both-side of the equation by 2520

48×2520 = 269.5Ф

120960 = 269.5Ф

divide both-side of the equation by 269.5

448.8≈Ф

Ф = 448.8°

The angle it turns through if it  sweeps an area of 48 cm²   is   448.8°