Name
Date
Pd
Unit VIII: Worksheet 1
For each problem draw a free-body diagram, a force diagram, and solve for the variables listed. The 𝜃, 𝐹,
and 𝑟 asked for are those used to calculate the torques. Some problems have more than one set of
variables. For those with only one set, cross out the second set of variables.
1.
Bar has a length of
10m and is pulled
with 15N. Rope has a
length of 12m. Both
the bar and rope are
massless.
2.
Bar has a length of 10m and
is pulled with 15N. Rope has
a length of 8m. Both the bar
and rope are massless.
60
3.
4.
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
0
The child and swing have
a mass of 50 kg. The
swing is pushed with a
force of 65N at an angle
of 400 with the
horizontal.
The child and swing have
a mass of 30 kg. The
swing is held with a force
of 25N at an angle of 200
with the horizontal.
5.
The 1 kg gears with a radius of
8 cm are held in place by two
aluminum bars as shown. the
chain comes off of the gear
assembly at a 50 angle.
6.
The 2m bar has an evenly
distributed mass of 2 kg.
The man pulls down on the
rope with 30N.
300
7.
8.
The massless U-shaped bar is
pulled straight back with 100
N.
The 4 kg plank is pushed
up with 60 N. The plank is
6 m long. 1 m from the end
of the plank rests a 2 kg
box.
250
9.
A 75 kg firefighter is 6m up
an 8m ladder. The ladder
has a mass of 20 kg. There
is friction between the ladder
and the ground, and no
friction between the ladder
and the building.
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
𝐹=
𝐹=
𝑟=
𝑟=
𝜃=
𝜃=
𝜏=
𝜏=
10. For each of the following diagrams, explain if the rod will rotate positively or negatively and explain
your answer. Each hand pulls with equal force.
a.
b.
c.
D
C
11. Explain which way should you pull on the wrench to create maximum torque.
B
A
12. Where should the door handle be placed in order to make it easiest to open and close the door?
Explain.
E