A car is traveling at 25 m/s when suddenly it brakes to stop. If the car stops in a distance of 12 m, at what rate is the car accelerating?
回答 (2)
2017-09-03 12:06 am
Initial velocity, u = 25 m/s
Final velocity, v = 0 m/s
Displacement, s = 12 m
v² = u² + 2as
0 = 25² + 2a(12)
24a = -625
acceleration, a = -26 m/s²
(The negative sign means that the direction of acceleration is opposite to the direction of movement of the car.)
Final velocity, v = 0 m/s
Displacement, s = 12 m
v² = u² + 2as
0 = 25² + 2a(12)
24a = -625
acceleration, a = -26 m/s²
(The negative sign means that the direction of acceleration is opposite to the direction of movement of the car.)
2017-09-03 12:02 am
v² = u²+2as
a = (v²-u²)/2s = (0-25²)/2(12) = -26 m/s²
Negative sign denotes decelaration
a = (v²-u²)/2s = (0-25²)/2(12) = -26 m/s²
Negative sign denotes decelaration
收錄日期: 2021-04-18 17:51:45
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