Uploaded by sarah12sarah12

newtonslawshomework2-answers

advertisement
Tuscarora High School 2013-2014
Newton's Laws Homework Set 2 - Tension and Pulleys
[Chapter 4] Numbers in brackets indicate a corresponding question in your textbook
1. [67] In the drawing, the weight of the block on the table is 422 N and that of the hanging block is 185 N. Ignore
all frictional effects and assuming the pulley to be massless.
a. Draw a Free-Body Diagram for each block
2
b. Determine the acceleration of the two blocks 2.987 m/s
c. Determine the tension of the cord 128.615 N
2. [84] As part “a” of the drawing shows, two blocks are connected by a rope that passes over a set of pulleys. One
block has a weight of 412 N, and the other has a weight of 908 N. The rope and the pulleys are massless and
there is no friction.
a. Draw free body diagrams for the blocks in part “a” of the diagram below.
2
b. What is the acceleration of the lighter block? 3.682 m/s
---c. Suppose that the heavier block is removed, and a downward force of 908 N is provided by someone
pulling on the rope, as part “b” of the drawing shows. Draw a FBD for the remaining block.
2
d. Find the acceleration of the remaining block. 11.798 m/s
e. Explain why the answers of “a” and “b” are different. Same net force, different mass of the system
3. [102] The drawing shows box 1 resting on a table, with box 2 resting on top of box 1. A massless rope passes
over a massless, frictionless pulley. One end of the rope is connected to box 2 and the other end is connected to
box 3. The weights of the three boxes are W1 = 55 N, W 2 = 35 N, and W3 = 28 N. Determine the magnitude of
the normal force that the table exerts on box 1. 62 N