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# Can speed be negative

Updated: 9/27/2023

Wiki User

12y ago

Yes in a form. It can not be literaly -20mph but in deceleration it is. when you slow down a car to a stop that is negative volocity. and volacity is speed+direction. ex: 30mph east. so if your travaling 20mph west then slow to a stop it changes to -20mph west. (until you start going east) but because volacity is a messure of speed then yes it is possible. but not like when approching the speed of light when time slows down, if you go slower than it by so much then it speeds up. (because the speed cant be that form and has to be in directiog)

Wiki User

12y ago

Wiki User

7y ago

The problem here is the conflating of the term "speed" with "velocity".

Velocity is a vector - it has both intensity and direction. Velocity can be negative.

Speed really only has magnitude, so it is normally only positive; since there is no direction associated you can't define a meaning for negative speed (unless you decide to define it as synonymous with velocity)

When a body is thrown in upward direction and upward motion is defined as positive velocity, its velocity decreases with time and at highest point speed and velocity become zero. When the body falls downward its speed i increases until hit the ground but since it is moving in the opposite of the direction that was defined as "positive", its velocity is negative.

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### Is it possible to travel at a negitave speed?

Negative speed isn't possible, but negative velocity is.

### Can the speed of the particle ever be negative if so give an example if not explian why?

see speed cannot de negative se speed = distance / time and neithr distance nor time can be negative they r always positive so speed cannot be negative but velocity can be negative

### Why is retardation called negative acceleration?

retardation is nothing but the decrease in speed. so if the increase in speed can be taken as positive then for sure decrease in speed can be taken as negative acceleration.

### What is negative speed in science?

Speed in science means vector (direction and velocity). Any force which lessens the vector can be considered negative speed. A spacecraft's retro rockets are a good example.

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Negative slope on a speed/time graph indicates decreasing speed. (Some call it "deceleration", although I wish they wouldn't.)

### Why can velocity be negative but nonzero speed is always positive?

speed is a scalar quantity with magnitude only but no direction; velocity is a vector with both magnitude (speed) AND direction, which could be positive or negative

### What happens to acceleration when speed decreases on a speed time graph?

Acceleration is negative.

### Can a speed of a body be negative?

The 'speed' of a body cannot be negative. But if you are stating the 'velocity' then it can be negative. Negative velocity means it is going opposite to the direction that you decided to call the positive direction.

### Is it possible to have a negative speed?

No, Speed is always greater than or equal to zero. However, velocity can be negative, which just means you have a positive speed in the opposite direction! (scalar(number) versus vector).

### Can the speed of the particle ever be negative if so give an example if not explain why?

speed cannot as it is just a magnitude, however as velocity relates both magnitude and direction, and direction can be negative, technically you can have a negative velocity.

### If your speed changes from 10 kmh to 6 kmh you have a(n) acceleration. positive or negtive?

if your speed is in the positive direction you are slowing down and acceleration is the opposite direction and is negative acceleration.However if your speed is the negative direction ( like running backwards) and you slow down then acceleration is in the opposite direction and positive.In your case if speed is 10 kmh positive going to 6kmh then acceleration is negative

### What is negative accelertion?

Acceleration is any change in velocity. Negative acceleration is when the change is such that the speed decreases.