Identify the situations that have an unbalanced force. check all that apply. a weight speeds up as it falls through the air a garbage can is at rest on the ground a hockey puck moves in a straight line at a constant speed a bumper car hit by another car moves off at an angle a balloon flies across the room when the air is released

the answer is1,4,5

A weight speeds up as it falls through the air.

A bumper car hit by another car moves off at an angle.  

A balloon flies across the room when the air is released.

Explanation:

An object accelerates when unbalanced force acts on it that is some net non zero force acts on it.  

With balanced force, i.e. the net zero force, the object is at rest or moves in straight line at constant speed.

The given situations that have an unbalanced force acting on it are:

A weight speeds up as it falls through the air - the weight accelerates as it falls towards ground.

A bumper car hit by another car moves off at an angle- the cars collide, unbalanced force causes the direction of the car to change

A balloon flies across the room when the air is released - when air is released, an equal of force acts on the balloon in opposite direction and thus it flies.