Projectile Motion
Dynamics · FE Reference Handbook section
Handbook notes for this section
Definitions and conditions exactly as the handbook states them.
- The equations for common projectile motion may be obtained from the constant acceleration equations as
Core formulas for this FE topic
Definitions, applicability, units, assumptions and worked examples for each relation.
Worked exam-style examples
The four ways this section is written on the real exam — thoughts first, then equations, then substitution.
A dynamics problem uses Projectile range. Given launch speed (v0) = 41.0000 m/s; launch angle (theta) = 61.0000 deg, determine the range (R) in m.
Given
Find
range (R), in m
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except R is given, so isolate R symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that R stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning R = 145.3 m to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 290.6 — kept a factor of two that cancels in the correct rearrangement.
- 72.6590 — dropped that same factor in the other direction.
- 159.8 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch angle (theta) = 67.0000 deg; range (R) = 134.5 m, determine the launch speed (v0) in m/s.
Given
Find
launch speed (v0), in m/s
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except v0 is given, so isolate v0 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that v0 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning v0 = 42.8281 m/s to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 85.6562 — kept a factor of two that cancels in the correct rearrangement.
- 21.4140 — dropped that same factor in the other direction.
- 47.1109 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch speed (v0) = 16.5000 m/s; launch angle (theta) = 65.0000 deg, determine the range (R) in m.
Given
Find
range (R), in m
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except R is given, so isolate R symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that R stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning R = 21.2595 m to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 42.5190 — kept a factor of two that cancels in the correct rearrangement.
- 10.6297 — dropped that same factor in the other direction.
- 23.3854 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch angle (theta) = 27.0000 deg; range (R) = 18.8000 m, determine the launch speed (v0) in m/s.
Given
Find
launch speed (v0), in m/s
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except v0 is given, so isolate v0 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that v0 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning v0 = 15.0985 m/s to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 30.1971 — kept a factor of two that cancels in the correct rearrangement.
- 7.5493 — dropped that same factor in the other direction.
- 16.6084 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch speed (v0) = 46.0000 m/s; launch angle (theta) = 11.0000 deg, determine the range (R) in m.
Given
Find
range (R), in m
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except R is given, so isolate R symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that R stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning R = 80.8020 m to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 161.6 — kept a factor of two that cancels in the correct rearrangement.
- 40.4010 — dropped that same factor in the other direction.
- 88.8822 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch angle (theta) = 60.0000 deg; range (R) = 128.4 m, determine the launch speed (v0) in m/s.
Given
Find
launch speed (v0), in m/s
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except v0 is given, so isolate v0 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that v0 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning v0 = 38.1375 m/s to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 76.2749 — kept a factor of two that cancels in the correct rearrangement.
- 19.0687 — dropped that same factor in the other direction.
- 41.9512 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch speed (v0) = 34.5000 m/s; launch angle (theta) = 16.0000 deg, determine the range (R) in m.
Given
Find
range (R), in m
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except R is given, so isolate R symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that R stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning R = 64.2953 m to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 128.6 — kept a factor of two that cancels in the correct rearrangement.
- 32.1476 — dropped that same factor in the other direction.
- 70.7248 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch angle (theta) = 44.0000 deg; range (R) = 268.9 m, determine the launch speed (v0) in m/s.
Given
Find
launch speed (v0), in m/s
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except v0 is given, so isolate v0 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that v0 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning v0 = 51.3762 m/s to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 102.8 — kept a factor of two that cancels in the correct rearrangement.
- 25.6881 — dropped that same factor in the other direction.
- 56.5139 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch speed (v0) = 29.0000 m/s; launch angle (theta) = 65.0000 deg, determine the range (R) in m.
Given
Find
range (R), in m
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except R is given, so isolate R symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that R stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning R = 65.6721 m to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 131.3 — kept a factor of two that cancels in the correct rearrangement.
- 32.8361 — dropped that same factor in the other direction.
- 72.2393 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion
A dynamics problem uses Projectile range. Given launch angle (theta) = 19.0000 deg; range (R) = 253.2 m, determine the launch speed (v0) in m/s.
Given
Find
launch speed (v0), in m/s
Start with the thinking
- The governing relation printed in this handbook section is Projectile range.
- Everything except v0 is given, so isolate v0 symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Dynamics items reward recognising the unknown before touching a calculator.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange the relation so that v0 stands alone on the left-hand side.
Step 3
Step 4 — Substitute the given values into the rearranged relation.
Step 5 — Evaluate:
Step 6 — Check: returning v0 = 63.5178 m/s to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 127.0 — kept a factor of two that cancels in the correct rearrangement.
- 31.7589 — dropped that same factor in the other direction.
- 69.8696 — rounded an intermediate value before the final step.
Reference: FE Reference Handbook — Dynamics → Projectile Motion