How to move ball speedily on the screen using box2d in libGDX?

package com.badlogic.box2ddemo;

import com.badlogic.gdx.ApplicationListener;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.GL10;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.Sprite;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.graphics.g2d.TextureRegion;
import com.badlogic.gdx.math.Matrix4;
import com.badlogic.gdx.math.Vector2;
import com.badlogic.gdx.physics.box2d.Body;
import com.badlogic.gdx.physics.box2d.BodyDef;
import com.badlogic.gdx.physics.box2d.BodyDef.BodyType;
import com.badlogic.gdx.physics.box2d.Box2DDebugRenderer;
import com.badlogic.gdx.physics.box2d.CircleShape;
import com.badlogic.gdx.physics.box2d.Fixture;
import com.badlogic.gdx.physics.box2d.FixtureDef;
import com.badlogic.gdx.physics.box2d.PolygonShape;
import com.badlogic.gdx.physics.box2d.World;

public class Box2DDemo implements ApplicationListener {

    private SpriteBatch batch;
    private TextureRegion texture;
    private World world;
    private Body groundDownBody, groundUpBody, groundLeftBody, groundRightBody,
            ballBody;
    private BodyDef groundBodyDef1, groundBodyDef2, groundBodyDef3,
            groundBodyDef4, ballBodyDef;
    private PolygonShape groundDownPoly, groundUpPoly, groundLeftPoly,
            groundRightPoly;
    private CircleShape ballPoly;
    private Sprite sprite;
    private FixtureDef fixtureDef;
    private Vector2 ballPosition;
    private Box2DDebugRenderer renderer;
    Vector2 vector2;

    @Override
    public void create() {

        texture = new TextureRegion(new Texture(
                Gdx.files.internal("img/red_ring.png")));
        sprite = new Sprite(texture);
        sprite.setOrigin(sprite.getWidth() / 2, sprite.getHeight() / 2);
        batch = new SpriteBatch();

        world = new World(new Vector2(0.0f, 0.0f), false);

        groundBodyDef1 = new BodyDef();
        groundBodyDef1.type = BodyType.StaticBody;
        groundBodyDef1.position.x = 0.0f;
        groundBodyDef1.position.y = 0.0f;
        groundDownBody = world.createBody(groundBodyDef1);

        groundBodyDef2 = new BodyDef();
        groundBodyDef2.type = BodyType.StaticBody;
        groundBodyDef2.position.x = 0f;
        groundBodyDef2.position.y = Gdx.graphics.getHeight();
        groundUpBody = world.createBody(groundBodyDef2);

        groundBodyDef3 = new BodyDef();
        groundBodyDef3.type = BodyType.StaticBody;
        groundBodyDef3.position.x = 0f;
        groundBodyDef3.position.y = 0f;
        groundLeftBody = world.createBody(groundBodyDef3);

        groundBodyDef4 = new BodyDef();
        groundBodyDef4.type = BodyType.StaticBody;
        groundBodyDef4.position.x = Gdx.graphics.getWidth();
        groundBodyDef4.position.y = 0f;
        groundRightBody = world.createBody(groundBodyDef4);

        groundDownPoly = new PolygonShape();
        groundDownPoly.setAsBox(480.0f, 10f);

        fixtureDef = new FixtureDef();
        fixtureDef.density = 0f;
        fixtureDef.restitution = 1f;
        fixtureDef.friction = 0f;
        fixtureDef.shape = groundDownPoly;

        fixtureDef.filter.groupIndex = 0;

        groundDownBody.createFixture(fixtureDef);

        groundUpPoly = new PolygonShape();
        groundUpPoly.setAsBox(480.0f, 10f);

        fixtureDef = new FixtureDef();
        fixtureDef.friction = 0f;
        fixtureDef.restitution = 0f;
        fixtureDef.density = 0f;
        fixtureDef.shape = groundUpPoly;
        fixtureDef.filter.groupIndex = 0;

        groundUpBody.createFixture(fixtureDef);

        groundLeftPoly = new PolygonShape();
        groundLeftPoly.setAsBox(10f, 320f);

        fixtureDef = new FixtureDef();
        fixtureDef.friction = 0f;
        fixtureDef.restitution = 0f;
        fixtureDef.density = 0f;
        fixtureDef.shape = groundLeftPoly;
        fixtureDef.filter.groupIndex = 0;

        groundLeftBody.createFixture(fixtureDef);

        groundRightPoly = new PolygonShape();
        groundRightPoly.setAsBox(10f, 320f);

        fixtureDef = new FixtureDef();

        fixtureDef.friction = 0f;
        fixtureDef.restitution = 0f;
        fixtureDef.density = 0f;
        fixtureDef.shape = groundRightPoly;
        fixtureDef.filter.groupIndex = 0;

        groundRightBody.createFixture(fixtureDef);

        ballPoly = new CircleShape();
        ballPoly.setRadius(16f);

        fixtureDef = new FixtureDef();
        fixtureDef.shape = ballPoly;
        fixtureDef.density = 1f;
        fixtureDef.friction = 1f;
        fixtureDef.restitution = 1f;

        ballBodyDef = new BodyDef();
        ballBodyDef.type = BodyType.DynamicBody;
        ballBodyDef.position.x = (int) 200;
        ballBodyDef.position.y = (int) 200;

        ballBody = world.createBody(ballBodyDef);
         ballBody.setLinearVelocity(200f, 200f);
        // ballBody.applyLinearImpulse(new Vector2(250f, 250f),
        // ballBody.getLocalCenter());
        ballBody.createFixture(fixtureDef);

        renderer = new Box2DDebugRenderer(true, false, false);

    }

    @Override
    public void dispose() {
        ballPoly.dispose();
        groundLeftPoly.dispose();
        groundUpPoly.dispose();
        groundDownPoly.dispose();
        groundRightPoly.dispose();
        world.destroyBody(ballBody);
        world.dispose();
    }

    @Override
    public void pause() {
    }

    @Override
    public void render() {

        world.step(1f/30f, 3, 3);

        Gdx.gl.glClearColor(1f, 1f, 1f, 1f);
        Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);

        batch.begin();
        vector2 = ballBody.getLinearVelocity();

        System.out.println("X=" + vector2.x + " Y=" + vector2.y);

        ballPosition = ballBody.getPosition();
        renderer.render(world,batch.getProjectionMatrix());

        // int preX = (int) (vector2.x / Math.abs(vector2.x));
        // int preY = (int) (vector2.y / Math.abs(vector2.y));
        //
        // if (Math.abs(vector2.x) == 0.0f)
        // ballBody1.setLinearVelocity(1.4142137f, vector2.y);
        // else if (Math.abs(vector2.x) < 1.4142137f)
        // ballBody1.setLinearVelocity(preX * 5, vector2.y);
        //
        // if (Math.abs(vector2.y) == 0.0f)
        // ballBody1.setLinearVelocity(vector2.x, 1.4142137f);
        // else if (Math.abs(vector2.y) < 1.4142137f)
        // ballBody1.setLinearVelocity(vector2.x, preY * 5);

        batch.draw(sprite, (ballPosition.x - (texture.getRegionWidth() / 2)),
                (ballPosition.y - (texture.getRegionHeight() / 2)));

        batch.end();
    }

    @Override
    public void resize(int arg0, int arg1) {
    }

    @Override
    public void resume() {
    }

}

I implement above code but I can not achieve higher moving speed of the ball