In: Physics
A stonemason is dragging a 60-kg marble block 4 m across a floor by pulling on a rope attached to the block. He pulls with a horizontal force of 210 N. The coefficient of kinetic friction between the block and the floor is 0.30. The next five questions have to do with this scenario. Draw yourself a free-body diagram on the block.
How much work was done by the stonemason in dragging this block?
a. |
100 J |
|
b. |
560 J |
|
c. |
840 J |
|
d. |
1230 J |
Add up the y-components, ΣFy, and determine the normal force the floor exerts upward on the block.
a. |
588 N |
|
b. |
345 N |
|
c. |
279 N |
|
d. |
126 N |
Using your result from above, calculate the kinetic frictional force between the block and the floor.
a. |
45.6 N |
|
b. |
56.7 N |
|
c. |
98.5 N |
|
d. |
176.4 N |
Determine the work done by friction.
a. |
345.2 J |
|
b. |
-705.6 J |
|
c. |
-980.1 J |
|
d. |
1257.9 J |
Add up the x-components, ΣFx , and determine the block's acceleration.
a. |
3.7 m/s2 |
|
b. |
0.91 m/s2 |
|
c. |
0.56 m/s2 |
|
d. |
0.38 m/s2 |