# Box 2d SetLinearVelocity in 0 gravity

**URL:** https://forum.kirupa.com/t/box-2d-setlinearvelocity-in-0-gravity/309407
**Category:** flash
**Created:** [May 14, 2010, 5:33am UTC](https://forum.kirupa.com/t/box-2d-setlinearvelocity-in-0-gravity/309407 "2010-05-14T05:33:16Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![sebby64](https://avatars.discourse-cdn.com/v4/letter/s/71c47a/32.png) [@sebby64](https://forum.kirupa.com/u/sebby64)
#### Post date: [May 14, 2010, 5:33am UTC](https://forum.kirupa.com/t/box-2d-setlinearvelocity-in-0-gravity/309407/1 "2010-05-14T05:33:16Z")

</div>

I am using Box2d 2.02, and am having trouble with setting linear velocity of a body in 0 gravity. When I trace GetLinearVelocity() when left is pressed, it reports the correct vector (-20.0, 0.0) but the body does not move. It is a dynamic body. Is there anything I’m missing?

```auto
if (Key.isDown(Keyboard.LEFT)) {
                
                if (mover.IsSleeping()){
                    mover.WakeUp();
                }
                mover.SetLinearVelocity(new b2Vec2( -20.0, 0.0));

            }

```