Ball Falling very slowly (How to Fix?)

I am trying to make ball jumping program but every time I try Jumping the ball falls
very slowly. Here is my code:

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#pragma strict 

var rotationSpeed = 100;

var jumpHeight = 15;

var jumpHeigtht2 = 0;

var isFalling = false;



function Update ()

{

// this is to Handle the Ball rotation.

var rotation : float = Input.GetAxis("Horizontal") * rotationSpeed;
 

rotation *= Time.deltaTime;

GetComponent(Rigidbody).AddRelativeTorque(Vector3.back * rotation);



// this is to help the ball jump.

if (Input.GetKey(KeyCode.W)&& isFalling == false)

{ 

GetComponent(Rigidbody).velocity.y = jumpHeight;

}

else

{

GetComponent(Rigidbody).velocity.y = jumpHeigtht2;

}

}

 

function OnCollisionStay ()

{ 

isFalling = false;

}

 

function OnCollisionExit ()

{ 

isFalling = true;

}
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Try getting rid of the line

GetComponent(Rigidbody).velocity.y = jumpHeigtht2;

I don’t think you need it.

Does the ball have a RigigdBody? If not add one to it and try. If it is still slow the default gravity on the rigid body is 1, change it to 2 and so on.