# Can decreasing acceleration be negative acceleration ?

1. Oct 5, 2012

### Celluhh

Can decreasing acceleration be negative acceleration ?

2. Oct 5, 2012

### rock.freak667

Re: Acceleration

Yes a decelerating body will have a negative acceleration.

3. Oct 5, 2012

### Celluhh

Re: Acceleration

No deceleration is constant not decreasing acceleration

4. Oct 5, 2012

### Staff: Mentor

Re: Acceleration

Decreasing acceleration can be, but does not need to be, negative acceleration.

Example #1: decreasing and negative:

t = 0, a = -1
t = 2, a = -2
t = 3, a = -3

Example #2: decreasing and positive:

t = 0, a = 5
t = 1, a = 4
t = 2, a = 3

5. Oct 6, 2012

### Celluhh

Re: Acceleration

Yeah exactly I agree With you but my teacher insists that I am wrong and claims that decreasing acc cannot be negative acc. Whew !! At least someone has the same thinking as me .

6. Oct 6, 2012

### Celluhh

Re: Acceleration

Erm but for your first example acc is increasing right ?

7. Oct 10, 2012

### D_DaYwAlKeR

Re: Acceleration

@Celluhh
since, acceleration is a vector..it can be negative...

If the acceleration is against the velocity of the particle..then it is said to be a negative acceleration...
the sign "negative" simply indicates that acceleration is opposite to velocity vector...
the "negative" sign has nothing to do with the magnitude of the acceleration ...a negative acceleration just means that it is opposite to the direction of motion..