Balanced and Unbalanced Forces

Two forces are applied to a 17 kg box, as shown. The box is on a smooth surface.

Which statement best describes the acceleration of the box?

• The box accelerates upward.

  
  

• The box accelerates to the right.

  
  

• The box accelerates to the left.

  
  

• The box does not accelerate.

  
  

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

What is the net force

• 10 N to the right

• 30 N to the right

• 10 N to the left

• 30 N to the left

Tags

NGSS.MS-PS2-2

What is the net force?

• 15 N

• 5 N to the left

• 5 N to the right

• 15 N left

Tags

NGSS.MS-PS2-2

What is the net force?

• 38 N to the left

• 38 N to the right

• 2 N to the left

• 2N to the right

Tags

NGSS.MS-PS2-2

The ball pictured is at rest. What statement below describes the forces at work?

• there are no forces acting on the ball

  
  

• none of the above

  
  

• the forces are balanced

  
  

• the forces are unbalanced

  
  

Tags

NGSS.HS-PS2-1

What is a force?

• A touch

• Any push or pull

• Power or energy

• Gravity only

Answer explanation

A force pushes or pulls on an object. One example is gravity. Another is friction. Forces can cause changes in motion, such as stopping, starting, speeding up, slowing down or changing direction.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

What is inertia?

• Objects changing their motion on their own.

• Objects moving in a straight line.

• Objects staying still when they are acted on by a force.

• Objects not changing motion unless acted on by an unbalanced force.

Answer explanation

"Inertia" is the tendency of objects to follow Newton's first law: Objects in motion remain in motion and objects at rest remain at rest unless acted on by an unbalanced force.

Tags

NGSS.MS-PS2-2

 What is the unit that measures force?

• Weight
• Net force
• Newton
• Kilogram

Newton’s first law of motion: An object at rest remains at rest unless acted on by an _________.

• Unbalanced Force.

• Act of Inertia

• Angry Dog

• Unknown Force

Inertia is the tendency of an object to _____ change in its motion.

• Keep

• Resist

• Add

• Look for