help with error CS0246

Assets/script/player controller.cs(16,10): error CS0246: The type or namespace name `PlayerPhysics' could not be found. Are you missing a using directive or an assembly reference?

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using UnityEngine; using System.Collections;

[RequireComponent(typeof(playerphysics))] public class Playercontroller : MonoBehaviour {

//Player Handling public float gravity = 20; public float speed = 8; public float acceleration = 12;

private float currentSpeed; private float targetSpeed; private Vector2 amountToMove;

private PlayerPhysics playerPhysics;

void Start() { PlayerPhysics = GetComponent(); }

void Update() { targetSpeed = Input.GetAxisRaw("Horizontal") * speed; currentSpeed = IncrementTowards(currentspeed, targetSpeed,Acceleration);

 amountToMove.x = currentSpeed;
 amountToMove.y -= gravity * Time .deltaTime;
 playerphysics.Move(amountToMove * Time.deltaTime);

}

 //increase n towards target by speed
 private float IncrementTowards(float n, float target, float a) {
      if (n == target) {
          return n;
     }
     else {
         float dir = Mathf.Sign(target - n); //must n be increased or decreased to get closer to target
         n += a * Time.deltaTime * dir;
         return (dir == Mathf.Sign(target-n))? n: target; //if n has now passed target then return target, otherwise
     }

} }