Practical: projectile range at various angles
G5.2 G1.5
By the end of this lesson you should be able to
- Investigate the horizontal distance travelled by an object projected at various angles from the horizontal. G5.2
- Interpret data relating to the horizontal distance travelled by an object projected at various angles from the horizontal. G1.5
Key ideas
- Aim: investigate how horizontal distance depends on launch angle (G5.2).
- Independent variable: launch angle. Dependent: horizontal range. Controlled: launch speed, launch height, projectile.
- Take at least 3 trials per angle; report the mean ± (max − min)/2.
- Analysis: plot range vs sin 2θ with error bars, draw best-fit and worst-fit lines, and use the gradient (u²/g) to find the launch speed.
- Evaluate: air resistance, launch height above the landing point, consistency of launch speed.
Key formulas (QCAA formula book notation)
\[
\text{range} = \frac{u^2}{g}\sin 2\theta \Rightarrow \text{gradient} = \frac{u^2}{g}
\]
Common mistakes
- Too few angles near 45° to see the peak.
- Not measuring range from directly below the launch point.
Do
- Read: Textbook (Oxford Physics for Queensland Units 3 & 4) section 2.4
- Do: Practical 2.4 questions
- Data skills: Data test skills and practice
Try it
Further reading
- OpenStax Physics 5.3 Projectile motion (OpenStax, CC BY 4.0)
- Full topic notes: Gravity & Motion