Acceleration is defined by physics as the rate of change of velocity over time.
a = dv/dt
As time changes, any change in velocity results in a change in acceleration.
That change can be positive or negative.
If you want to know why, its because acceleration and velocity are vectors.
A vector has a magnitude and a direction.
The magnitude is the value, and the direction refers to the direction the object is traveling.
An example when acceleration doesn't point in the same direction as velocity is when you throw a ball into the air.
You throw it up, so the initial velocity is in the upward direction.
However the acceleration due to gravity is downward.
It will slowly decrease the upward velocity of the ball until it is zero.
At that point the ball will start to fall downard and increase in velocity until it hits the ground.
This is a moving object that is slowing down.
Acceleration doesn't mean "speeding up". It only means that the speed or direction of motion, or both, are changing. Speeding up is positive acceleration in the direction you're moving. Slowing down is negative acceleration in the direction you're moving, or positive acceleration in the opposite direction.
No, retardation refers to a negative acceleration, which means the object is slowing down. A zero acceleration means the object is moving at a constant velocity.
Acceleration is negative if the object is slowing down or moving in the opposite direction of the velocity vector.
The acceleration is opposite the direction the object is moving, so the acceleration is negative and southward.
Acceleration is the change of velocity, with direction. Therefore slowing down is a change in veolcity, so is considered to be acceleration (just negative acceleration).
This is a moving object that is slowing down.
An object slowing down can have an acceleration that is not negative if it is moving in the opposite direction of its velocity. In this case, the acceleration would be in the same direction as the object's motion, even though it is slowing down. This can happen, for example, when an object is moving in the positive direction but experiencing a negative acceleration due to a force in the negative direction.
Acceleration doesn't mean "speeding up". It only means that the speed or direction of motion, or both, are changing. Speeding up is positive acceleration in the direction you're moving. Slowing down is negative acceleration in the direction you're moving, or positive acceleration in the opposite direction.
When a moving object is slowing down, i.e. its speed is decreasing.
No, retardation refers to a negative acceleration, which means the object is slowing down. A zero acceleration means the object is moving at a constant velocity.
Acceleration is negative if the object is slowing down or moving in the opposite direction of the velocity vector.
The acceleration is opposite the direction the object is moving, so the acceleration is negative and southward.
The two components of acceleration are magnitude (how fast an object is speeding up or slowing down) and direction (the way in which the object is moving).
If the object is moving in a positive direktion along its x-axis and the acceleration is in the opposite direction (negative acceleration, i.e. retardation), then yes. Lets say the acceleration is -2 m/s^2 and its increasing with a magnitude of 2 then the new acceleration would be -4 m/s^2. Sure, the object was already slowing down but now its slowing down even more.
When a moving object experiences negative acceleration, it means that its velocity is decreasing over time. This could be due to the object slowing down, changing direction, or coming to a stop. Negative acceleration is commonly referred to as deceleration.
If the object is moving in a positive direktion along its x-axis and the acceleration is in the opposite direction (negative acceleration, i.e. retardation), then yes. Lets say the acceleration is -2 m/s^2 and its increasing with a magnitude of 2 then the new acceleration would be -4 m/s^2. Sure, the object was already slowing down but now its slowing down even more.