Auto stopping distance
Under optimum conditions on a dry road, the coefficient of friction may be as high as 0.8, so that you could decelerate at 0.8g = 0.8 x 9.8 m/s^2 = 7.8 m/s^2.
All constant acceleration problems can be solved using the basic motion equations.
In the equation, v is the velocity at a chosen time t. In this problem the initial velocity is given, and you know that v=0 since it is the velocity at the time when you stop.
Examining the known and unknown quantities
b. The stopping distance may be calculated from the motion equation:
Alternatively, the distance may be calculated from the combined motion equation form which eliminates the time from the calculation.
Motion with constant acceleration
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