Unity Programming Certification

An error is being thrown when setting the velocity of the RigidBody2D in the Update() method.

The error produced states the following: CS1955 C# Non-invocable member 'Vector2' cannot be used like a method.

Select the appropriate options in the dropdown menus that would fix the error.

​ (a)  

• Choose One
• new
• void
• () =>

Answer explanation

When using a Vector2 object, you must instantiate it using the "new" kekyword

You want to be able to call the actionBtPressed() method from your player object. What is the appropriate access modifier and return type that the method should have? Select the appropriate option from the dropdown menu.​ (a)  

• Choose One...
• void
• public
• virtual
• private
• accessible

Answer explanation

The access modifier needed for the actionBtPressed() method is public.

Based on the API definition, select the correct implementation of the AddForce() function from the dropdown menu.

Rigidbody.AddForce

public void AddForce(float x, float y, float z, ForceMode mode = ForceMode.Force);

Parameters:

∎x Size of force along the world x-axis.

∎y Size of force along the world y-axis.

∎z Size of force along the world z-axis.

∎mode Type of force to apply.

Description:

Adds a force to the Rigidbody.

Force is applied continuously along the direction of the x,y, and z vectors. Specifying the ForceMode mode allows the type of force to be changed to an Acceleration, Impuls, or Velocity Change.

Force can be applied only to an active Rigidbody. If a GameObject is inactive, AddForce has no effect.

By default, the Rigidbody's state is set to awake once a force is applied unless the force is Vector3.zero.​ ​ (a)  

• Choose One...
• AddForce(0, 0, thrust, ForceMode.Impulse);
• AddForce("0", "0", thrust, ForceMode.Impulse);
• AddForce(0, 0, ForceMode.Impulse);

Your current task is to create a script that will start an attack animation and instantiate a projectile when the play presses a button on the keyboard. Drag the appropriate code snippets to the correct place in the code block.

a

b

c

Input.GetKeyDown(KeyCode.Space)

anim.SetBool("ThrowSpear", true);

Input.GetMouseButtonDown(0)

Instantiate(spear, projectileStartPos.t)

anim.Trigger("Walk");

Input.GetMouseButton(0) returns true if the left mouse button is held down.

• True

• False

Input.GetMouseButtonDown(1) returns true if the middle mouse button was pressed.

• True

• False

Input.GetMouseButtonUp(2) returns true if the right button was released.

• True

• False

You want to write a log message to the console to check if a key was pressed. Select the correct way to write a debug log message.​ (a)  

• CHoose One...
• Debug.Log("Space key was pressed!");
• Console.Log("Space key was pressed!");
• Unity.Log("Space key was pressed!");
• System.Log("Space key was pressed!");

You just got an error message that says "NullReferenceException: Object reference not set to an instance of an object." Which object is likely null?

• myName

• myPos

• Debug.Log

• enemy

Given the line of code below, select the generic syntax of the GameObject.AddComponent() API.

SphereCollider sc = gameObject.AddComponent(typeof(SphereCollider)) as SphereCollider;

• SphereCollider sc = gameObject.AddComponent SphereCollider;()

• SphereCollider sc = gameObject.AddComponent<SphereColleder>

• SphereCollider sc = gameObject.AddComponent(SphereCollider)() as SphereCollider;

• SphereCollider sc = gameObject.AddComponent<SphereCollider>() as SphereCollider;