If you double your speed, your stopping distance increases by how many times?

If you double your speed, your stopping distance increases by how many times?

• A. Two times
• B. Four times
• C. Eight times
• D. Same distance

Answer: (B)

The main idea is that stopping distance grows with the square of speed. When you double how fast you’re going, the distance needed to stop increases fourfold, assuming your braking capability stays the same. This comes from the fact that stopping distance is tied to the energy you must dissipate, which scales with velocity squared. So doubling speed makes the braking distance about four times longer. In real driving, total stopping distance also includes perception-reaction distance (which also increases with speed), so the overall distance can be even longer, but the braking portion specifically becomes four times larger when speed is doubled.

The main idea is that stopping distance grows with the square of speed. When you double how fast you’re going, the distance needed to stop increases fourfold, assuming your braking capability stays the same. This comes from the fact that stopping distance is tied to the energy you must dissipate, which scales with velocity squared. So doubling speed makes the braking distance about four times longer. In real driving, total stopping distance also includes perception-reaction distance (which also increases with speed), so the overall distance can be even longer, but the braking portion specifically becomes four times larger when speed is doubled.