Force & Motion

You and your dad are moving the couch from one side to another. Your dad pushes with a force of 35 N to the right and you push with a force of 25 N right. What is the net force on the couch?

• 60 N right
• 10 N left
• 60 n right
• 50 N left

What is the net force?

• 5000 N right
• 4000 N right
• 40 N left
• 4000 N left

__________ is the sum of all forces acting on an object. It is capable of accelerating a mass. 

• velocity
• gravity
• net force
• distance

What kind(s) of objects have inertia?

• all objects with mass
• only objects at rest
• only objects in motion
• only objects whose motion is being changed

Which type of force(s) will cause a change in an object's motion?

• gravity
• zero net force
• balanced forces
• unbalanced forces

Friction is a force that acts 

• in the same direction as the motion
• opposite to the direction of the motion
• opposite to the applied forces
• the same direction as the applied force

What is Newton's First Law

• F=ma
• Every action has an equal and opposite reaction
• An object at rest stays at rest, an object in motion stays in motion... 
• Friction 

After a cannonball is fired into frictionless space, the amount of force needed to keep it going equals

• twice the force with which it was fired
• the same amount of force with which it was fired
• 1/2 the force with which it was fired
• zero, since no force is requires to keep it moving. 

One object has twice as much mass as another object. The first object also has also twice as much...

• velocity
• gracitational acceleration
• inertia
• all of these

Which one needs a greater net force to move, a kilogram of feathers or a kilogram of iron?

• feathers

• iron

• They need the same force.

• It depends on their friction.