Honors Physics – Static Equilibrium and Torque Worksheet

Honors Physics – Static Equilibrium and Torque Worksheet
1. A uniform, 100-g meter stick is placed atop a
fulcrum positioned at 65 cm. Where would a
150-g mass be hung from the meter stick
such that it would be balanced? [75 cm]
2. The same meter stick as in the above
problem is now placed atop a fulcrum
positioned at 30 cm. The meter stick has a
20-g mass attached at 96 cm and a 100-g
mass attached at 22 cm. Where would a 200g mass be positioned such that the meter
stick is balanced? [17.4 cm]
6. A window washer is standing on a scaffold
supported by a vertical rope at each end. The
scaffold weighs 200 N and is 3.00 m long.
What is the tension in each rope when the
700-N worker stands 1.00 m from one end?
[567 N, 333 N]
A beam resting on two pivots has a length of
L = 6.00 m and a mass M = 90.0 kg. One
pivot is to the far left while the other is a
distance l = 4.00 m from the left edge of the
beam. A woman of mass m = 55.0 kg starts
walking along the beam as shown. At what
distance x from the left edge of the beam will
the woman be just as the beam starts to tip?
[5.63 m]
In the arrangement of tackle boxes and fish in
equilibrium, what is the mass of the fish?
Assume the bar is massless. [3.0 kg]
A 50-N bowling ball is held in a person’s hand
horizontally as shown above. Find the upward
force exerted by the biceps on the ulna, and
downward force exerted by the humerus on
the ulna. [583 N, 533 N]
5. A 50-N, 10-m long uniform ladder rests on the
side of a smooth vertical wall, and is held in
place by friction with the floor below. If the
ladder just starts to slip at a 50° angle with
the floor, what is the coefficient of friction
between the ladder and the floor? [0.420]
Hey Yogi! A hungry 700-N bear walks out on
a 6-m long, 200-N beam to get an 80-N pic-anic basket as shown. Note that the beam is
connected to the wall by a hinge. (a) If the
wire can support a maximum of 900 N, at
what distance x would the wire break? (b)
What is the tension T in the wire, and what
are the vertical and horizontal forces Hx and
Hy exerted by the hinge, when the bear is at
x = 1.00 m? [5.14 m, T = 343 N, Hx = 172 N,
Hy = 683 N]