A curved road of diameter `1*8` km is banked so that no friction is required at a speed of 30 `ms^(-1)`. What is the banking angle ?

Explanation

To find the banking angle of a curved road, we can use the formula for the banking angle, which is derived from the condition that no friction is required for a vehicle to navigate the curve at a certain speed.

### Step-by-Step Solution:

1. **Identify the given values:**
- Diameter of the road = 1.8 km = 1800 m
- Radius (R) = Diameter / 2 = 1800 m / 2 = 900 m
- Speed (V) = 30 m/s
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