An inclined plane makes an angle 30° above the horizontal. A projectile is projected from a point on the plane with fixed speed u. If β denotes the angle of projection measured with respect to the inclined plane itself, then the range along the plane is maximum for:
Options

Question

An inclined plane makes an angle 30° above the horizontal. A projectile is projected from a point on the plane with fixed speed u. If β denotes the angle of projection measured with respect to the inclined plane itself, then the range along the plane is maximum for:

Options

G1 Physics · Accepted Answer

For maximum range, the angle with the horizontal is θ_max = 45° + α/2. Since θ = α + β, we have β_max = θ_max - α = 45° - α/2. For α = 30°, β_max = 45° - 15° = 30°. Therefore option B is correct.