The car requires 192 ft to stop from a speed of 48 mph
Explanation:
Given:
Speed, u = 30 mph
Stopping distance, d = 75 feet
The stopping distance d of a car after the brakes are applied varies directly as the square of the speed, u
So,
d = k (u)²
On substituting the value:
75 = k (30)²
k = [tex]\frac{75}{900} \frac{ft hr^2}{miles^2}[/tex]
Speed, u₂ = 48 mph
d₂ = ?
d₂ = k (u₂)²
On substituting the values we get:
d₂ = [tex]\frac{75}{900} X (48)^2[/tex]
d₂ = 192 ft
