Calculator Suite
Displacement Calculator
Calculate displacement, initial velocity, acceleration, or time using s = ut + ½at²
Common Scenarios
Projectile Motion
Object thrown upward - how far does it travel?
Elevator Motion
How far does an accelerating elevator travel?
Falling Object
How long to fall a certain distance?
Quick Presets
Primary Equation
Calculates displacement () given initial velocity (), time (), and acceleration ().
Alternative (No Time)
Useful when you know velocities and acceleration but not the time duration.
TL;DR
Displacement measures change in position (vector), not total distance traveled. Use this calculator to solve for displacement (), velocity (), time (), or acceleration ().
Distance vs. Displacement
Displacement is a vector, meaning it cares about direction. Distance is a scalar, meaning it only cares about "how much ground was covered."
How to Use This Calculator
- Select Goal: Choose which variable you need to find (e.g., "Displacement").
- Input Values: Enter the known variables (Initial Velocity, Time, Acceleration).
- Check Signs: Use positive numbers for one direction (e.g., Up) and negative for the other (e.g., Down).
- Review: Check the step-by-step derivation below the results.
Real-World Example: The "Running Track"
Scenario:
You run exactly one lap around a 400m track and end up where you started.
Analysis:
- Distance: 400 meters (total ground covered).
- Displacement: meters (final position - initial position = 0).
3 Key Checks (The "SOP")
Vector Check
Did you end up negative? That just means you are behind where you started.
Sign Check
Gravity pointing down? Make sure is negative (e.g., -9.81).
Time Check
Time cannot be negative. If you get , check your inputs.
Assumptions & Limitations
- Constant Acceleration: Formula assumes never changes.
- 1D Motion: This tool calculates motion along a straight line (1 dimension).
- Point Mass: Ignores the object's size and rotation.
Video Tutorials
Distance vs Displacement (Khan Academy)
Position-Time Graphs
Can displacement be negative?
Yes! Negative displacement simply means you ended up in the "negative" direction from where you started (e.g., behind the start line, or below the drop point).
What if calculated displacement is 0?
It means the object returned to its exact starting position. It definitely moved, but its net change in position is zero.
Why is it ½at² and not just at²?
This comes from calculus (integration). Visually, on a velocity-time graph, the distance is the area of a triangle, which is .