Newton's Laws

If the net force acting on any moving object is zero, the object will

• accelerate
• come to a stop
• continue in motion in a straight line
• move in a circular path

Which of the following is an acceptable unit for mass? 

• pounds
• kilograms
• Newton’s 
• tons

A box slides along a rough concrete surface and comes to a stop.  Which of the following best explains why the box comes to a stop?

• it is the natural tendency of an object in motion to come to a stop
• the concrete exerts a frictional force on the box that opposes its motion 
• there is no force pushing the box forward, so it stops
• the mass of the box causes it to slow down

Tags

NGSS.MS-PS2-2

The Free Body Diagram above shows the forces acting on a hockey puck in motion to the right.  Which of the following describe the motion of the hockey puck?

• the hockey puck moves to the right with constant velocity
• the hockey puck is slowing down
• the hockey puck is speeding up
• the hockey puck moves is a circle

A group of pirates fire a cannon.  They notice that when a cannon ball is fired from the cannon, the cannon rolls backwards.  The cannon is much more massive than the cannon-ball. 
Which of the following best explains why the cannon rolls backwards?

• the force that is exerted on the cannon ball is so great some is reflected back on   the cannon 
•  the inertia of the cannon causes it to roll backwards when the mass changes 
• the cannon ball’s energy is released to the cannon
• there is an equal force on the cannon but in the opposite direction of the force on the cannon-ball. 

A group of pirates fire a cannon.  They notice that when a cannon ball is fired from the cannon, the cannon rolls backwards.  The cannon is much more massive than the cannon-ball. 
Compared to the acceleration of the cannon ball, the acceleration of the cannon is

• greater
• equal
• less than
• cannot be determined

A 400 N girl standing on a dock exerts a force of 100 N on a 10,000 N sailboat as she pushes it away from the dock. How much force does the sailboat exert on the girl?  

• 25 N 
• 100 N 
•  400 N
• 10,000 N

A group of students are pulling a bucket of mass 10.0 kg from the bottom of the well by tying a rope to the bucket and pulling upwards. Use g = 10 m/s² to simplify calculations.
What is the weight of the bucket?

• 0
• 10
• 100
• 200

A group of students are pulling a bucket of mass 10.0 kg from the bottom of the well by tying a rope to the bucket and pulling upwards at a constant velocity
What is the free body diagram for this situation? 

• A
• B
• C
• D

A group of students are pulling a bucket of mass 10.0 kg from the bottom of the well by tying a rope to the bucket and pulling upwards.  Use g = 10 m/s² to simplify calculations.
How much upward force must the students exert to raise the bucket at a constant velocity?

• 0 N
• 100 N
• 120 N
• 200 N