The Flash — Speed Force

Real physics: from walking to 8.44× the speed of light. KE, drag, heat, and time dilation — all live.

relativitykinematicsthermodynamicssuperhero-science

Current Speed

301.1 m/s

NEAR-SUPERSONIC

1.00e-4% of c

WalkSoundSR-711% cc

Kinetic Energy

3.63 MJ

KE = ½mv²

Air Drag Force

8.33 kN

Fd = ½ρCdAv²

Leading-edge Temp

59.4 °C

Subsonic

Lorentz Factor γ

1.000000

Time dilation: t' = t/γ

Physics Breakdown

KE = ½ × m × v²

Flash weighs 80 kg. At this speed his kinetic energy is:

3.63 MJ

0.87 kcal of heat

½ × 80 kg × (301.1 m/s)² = 3.63 MJ

Baseball pitch (145 g @ 44 m/s)140.36 J
Car crash at 60 mph (1,500 kg)538.68 kJ
TNT — 1 kg (4.6 MJ)4.60 MJ
Hiroshima bomb (~6×10¹³ J)60.00 TJ
Flash at current speed3.63 MJ

Physics note

At relativistic speeds the classical formula underestimates KE. Correct relativistic KE = (γ−1)m₀c² = 3.63 MJ. (Negligible difference at this speed.)

Speed Timeline (Logarithmic — scroll right)

Walking
Usain Bolt
Cheetah
Formula 1
Sound (Mach 1)
SR-71 Blackbird
ISS Orbital
Escape Vel.
Parker Probe
1% light
The Flash
Light (c)
▲ YOU
1 m/sSound1% cc (light)

Treadmill Challenge

At 301.1 m/s, what can Flash accomplish?

Distance in 1 second

301 m

0.0008% of Earth's circumference

🌍

Time to circle the Earth

1.54 days

40,075 km circumference

🌕

Time to reach the Moon

14.78 days

384,400 km away

⚖️

Relativistic mass

80.00 kg

γ = 1.0000 (rest: 80 kg)

⏱️

Time dilation factor (γ)

1.000000

Negligible at this speed

🚀

Time to Mars (avg 225 Mkm)

8648.62 days

225,000,000 km average distance

Formula Reference

Kinetic Energy

KE = ½mv²

Classical (non-relativistic)

Air Drag Force

Fd = ½ρCdAv²

ρ=1.225 kg/m³, Cd=0.3, A=0.5 m²

Stagnation Temp

T★ = T₀(1 + 0.2M²)

Isentropic, γ=1.4 for air

Time Dilation

t′ = t / γ

γ = 1/√(1 − v²/c²)

⚡ SciFunLab · The Flash Speed Force Simulation · All physics values computed client-side in real time