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kbaker
Is there such a thing as negative acceleration?
Acceleration ia defined as a change in velocity over the change of time. According to that you can't have a negative velocity. The lowest you could be going is 0
YES , IF VELOCITY DECREASES .|dw:1355882836836:dw| THE SLOPE GIVES ACC. IE. -VE
well for example ,when you apply brakes suddenly on a vehicle that is called as retardation or negative of acceleration, in this case final velocity is less than the initial one so difference of final and initial is negative
negative acceleration or retardation means the rate of decrease of velocity with time
Yes...It is Deceleration...velocity decreases
Most people here don't understand acceleration, or at least haven't made the distinction between speed and velocity. You can have a negative acceleration and be speeding up. All the negative sign tells you is direction. For instance if you drop something off a building and you set it so that 0 was the ground and the top of the building was +10, then when you dropped it it would be accelerating downwards AND INCREASING speed. The velocity is the direction and speed, and it's an important distinction to make when understanding acceleration.
The term 'negative acceleration' is ambiguous. it can mean deceleration i.e. speed is decreasing OR It can mean that an object is accelerating in the negative direction. e.g. consider a stone thrown vertically upwards in the absence of air resistance. If one takes upwards as positive, the stone always has negative acceleration. BUT on its way upwards, it is decelerating, while on its way downwards, it is increasing its speed!