# Newton's Laws of Motion Review

## Navigate to:

Review Session Home - Topic Listing

Newton's Laws - Home  ||  Printable Version  ||  Questions with Links

Answers to Questions:  All  ||  #1-7  ||  #8-36  ||  #37-46  ||  #47-60

## Part E: Force-Mass-Acceleration Relationships

Construct free-body diagrams for the following objects; label the forces according to type. Use the approximation that g=10 m/s2
to determine the magnitude of all forces and the net force and acceleration of the object.

 38. A 2-kg box is at rest on a table.   ("At rest" would indicate a balance of forces and an acceleration of 0 m/s/s.) 39. A 2-kg box is free-falling from the table to the ground. ("Free-falling" indicates that the only force that influences the motion is the force of gravity.) 40. A 2-kg box equipped with a parachute is falling at a terminal velocity after being dropped from a plane. (A "terminal velocity" indicates a constant velocity and a balance of forces.)

 41. A 2-kg box is sliding to the right across a table. The force of friction upon the box is 5 N.   (Friction is directed opposite the motion and causes a leftward acceleration; no rightward force is spoken of, only a rightward motion.) 42. An 8-N force is applied to a 2-kg box to move it to the right across the table at a constant velocity of 1.5 m/s.   (A "constant velocity" indicates an acceleration of 0 m/s/s and a balance of forces.) 43. An 8-N force is applied to a 2-kg box to accelerate it to the right across a table. The box encounters a force of friction of 5 N. (The horizontal forces can be summed as vectors; divide by the mass to obtain the acceleration value.) 44. A 500-kg freight elevator is descending down through the shaft at a constant velocity of 0.50 m/s. (A "constant velocity" indicates an acceleration of 0 m/s/s and a balance of forces.) 45. A 500-kg freight elevator is moving upwards towards its destination. Near the end of the ascent, the upward moving elevator encounters a downward acceleration of 2.0 m/s/s.   (Begin by multiplying m•a to find the net force - 1000 N, down. The downward gravity force must be 1000 N more than the upward tension force.) 46. A 150-N rightward force is applied to a 20-kg box to accelerate it to the right across a rough surface at a rate of 2.0 m/s/s.   (Begin by multiplying m•a to determine the net force - 40 N, right. The rightward applied force must be 40 N more than the leftward friction force.)

 Useful Web Links Free-Body Diagrams || Finding Acceleration || Finding Individual Forces

#37 | #38 | #39 | #40 | #41 | #42 | #43 | #44 | #45 | #46 ]

## Navigate to:

Review Session Home - Topic Listing

Newton's Laws - Home  ||  Printable Version  ||  Questions with Links

Answers to Questions:  All  ||  #1-7  ||  #8-36  ||  #37-46  ||  #47-60

## You Might Also Like ...

Users of The Review Session are often looking for learning resources that provide them with practice and review opportunities that include built-in feedback and instruction. If that is what you're looking for, then you might also like the following:

The Calculator Pad includes physics word problems organized by topic. Each problem is accompanied by a pop-up answer and an audio file that explains the details of how to approach and solve the problem. It's a perfect resource for those wishing to improve their problem-solving skills.

2. Minds On Physics the App Series

Minds On Physics the App ("MOP the App") is a series of interactive questioning modules for the student that is serious about improving their conceptual understanding of physics. Each module of the series covers a different topic and is further broken down into sub-topics. A "MOP experience" will provide a learner with challenging questions, feedback, and question-specific help in the context of a game-like environment. It is available for phones, tablets, Chromebooks, and Macintosh computers. It's a perfect resource for those wishing to refine their conceptual reasoning abilities. Part 2 of the series includes Newton's Laws of Motion.

Visit: MOP the App Home || MOP the App - Part 2