Question

The range of a projectile, when launched at an angle of 30° with the horizontal is 2 km. What is the range of the projectile, when launched at an angle of 45° with the horizontal?

Options

• 0.75 km

• 1.5 km

• 2.3 km

• 6.0 km

Answer 1

2.3 km

Explanation:

R = `("u"^2sin2theta)/"g"`

For θ = 10°, R = 2 km

u² = `("Rg")/(sin2theta) = (2 xx 9.8)/sin60 = 22.6`

For θ = 45°

R = `(22.6 xx sin2(45^circ))/9.8 = (22.6 xx sin90^circ)/9.8 = 2.3` km