Physics Calculator: How to Calculate Force, Velocity, Acceleration, and Energy for Real-World Problems

Physics is all around you — from the force needed to push a car up a hill to the velocity of a baseball pitch or the energy consumed by a household appliance. Whether you are a student studying for an exam, a DIY enthusiast calculating loads, or a professional engineer, having instant access to physics formulas saves time and prevents errors. Use the Physics Calculator at Today Calculator to compute kinematic equations, force problems, energy values, and more in seconds.

1. Kinematics: Motion Calculations

Kinematics describes motion without considering forces. The four kinematic equations cover every motion scenario:

Equation	Solves For	Real-World Example
v = u + at	Final velocity	A car accelerates from 0 to 27 m/s in 6 s. Acceleration = 4.5 m/s²
s = ut + ½at²	Displacement	How far does a ball fall in 3 seconds? s = 0 + 0.5 × 9.8 × 9 = 44.1 m
v² = u² + 2as	Final velocity (no time)	A bike braking from 10 m/s over 20 m. What is final speed?
s = ½(u + v)t	Displacement (avg velocity)	A train moves at avg 15 m/s for 30 s. Distance = 450 m

2. Force and Newton’s Laws (F = ma)

Newton’s Second Law is the cornerstone of classical mechanics. Here are common force calculations:

Quantity	Formula	Common Units	Example
Force	F = ma	Newtons (N)	Push a 5 kg box at 4 m/s² → 20 N of force
Weight	W = mg	Newtons (N)	A 70 kg person weighs 686 N on Earth
Friction	F_f = μN	Newtons (N)	μ = 0.3, normal force = 50 N → 15 N friction
Momentum	p = mv	kg·m/s	A 1,000 kg car at 20 m/s has 20,000 kg·m/s momentum

3. Energy and Work Calculations

Energy calculations help you understand everything from how much work your body does climbing stairs to the kinetic energy of a moving vehicle:

• Kinetic Energy: KE = ½mv² — A 1,200 kg car at 25 m/s (56 mph) has 375,000 J of kinetic energy
• Potential Energy: PE = mgh — A 70 kg person climbing 5 m gains 3,430 J of potential energy
• Work: W = Fd cos(θ) — Pushing a 30 kg box 5 m across a floor with 50 N of force = 250 J of work
• Power: P = W/t — If you do 3,430 J of work climbing in 10 seconds, your power output is 343 W

4. Quick Reference: Common Physics Constants

Constant	Symbol	Value
Gravitational acceleration	g	9.81 m/s² (Earth surface)
Speed of light	c	3.0 × 10⁸ m/s
Universal gravitational constant	G	6.67 × 10⁻¹¹ N·m²/kg²
Density of water	ρ_water	1,000 kg/m³
Atmospheric pressure	1 atm	101,325 Pa

For instant results on any physics problem — kinematics, forces, energy, or motion — use the free Physics Calculator. Just enter your known values and get accurate answers immediately.