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17 votes
17 votes
.A car skid for 290 m. assuming that the car skidded to a stop with a constant

acceleration of -3.90 m/s2
, determine the speed of the car before it began to
skid

User Oyeme
by
2.4k points

1 Answer

26 votes
26 votes

Answer:

The speed of the car before it began to skid is 47.56 m/s.

Step-by-step explanation:

We can use kinematics to solve this problem.

We are given three known variables:

  • Δx = 290 m
  • a = -3.90 m/s²
  • v = 0 m/s (final velocity is 0 m/s because the car skids to a stop).

We can use this kinematic equation to solve for the initial velocity, v₀.

  • v² = v₀² + 2aΔx

Substitute the known variables into the equation.

  • (0)² = v₀² + 2(-3.9)(290)
  • 0 = v₀² - 2262
  • 2262 = v₀²
  • v₀ = 47.56 m/s

The speed of the car before it began to skid is 47.46 m/s.

User Nikita Shchypyplov
by
2.9k points