A woman who weighs 500 N stands on a 6.0-m-long board that weighs 100 N. The board is supported at each end. The support force at the right end is 3 times the support force at the left end. How far from the right end is the woman standing?
a. 4.8 m b. 2.1 m
c. 1.7 m d. 1.2 m
e. 3.9 m
[Ques. 2] A 650-N billboard worker stands on a 4.00-m scaffold weighing 600 N and supported by vertical ropes at each end. How far would the worker stand from one of the supporting ropes to produce a tension of 660 N in that rope?
a. 1.78 m b. 2.00 m
c. 1.90 m d. 0.06 m
e. 0.93 m
[Ques. 3] A meterstick is supported by a knife-edge at the 50.0-cm mark. Doug hangs masses of 0.48 and 0.76 kg from the 10-cm and 80-cm marks, respectively. Where should Doug hang a third mass of 0.25 kg to keep the stick balanced?
a. 64.4 cm b. 25.6 cm
c. 74.4 cm d. 35.6 cm
e. 50 cm
[Ques. 4] A 274-N uniform ladder, 11.0 m long, rests against a smooth vertical wall. The coefficient of static friction between ladder and floor is 0.400 . What minimum angle can the ladder make with the floor before it slips?
a. 84.3 b. 68.2
c. 21.8 d. 51.3
e. 11.3
[Ques. 5] A 60-kg man is one fourth of the way up a 10-m ladder that is resting against a smooth, frictionless wall. If the ladder has a mass of 25 kg and it makes an angle of 60 with the ground, find the force of friction of the ground on the foot of the ladder.
a. 1.4E+1 N b. 1.6E+2 N
c. 2.4E+2 N d. 2.7E+2 N
e. 4.2E+3 N
[Ques. 6] Tasha has mass 20 kg and wants to use a 5.0-m board of mass 12 kg as a seesaw. Her friends are busy, so Tasha seesaws by herself by putting the support at the system's center of gravity when she sits on one end of the board. How far is she from the support point?
a. 1.9 m b. 0.94 m
c. 4.1 m d. 3.1 m
[Ques. 7] A uniform bridge span weighs 70.0 kN and is 40.0 m long. An automobile weighing 15.0 kN is parked with its center of gravity located 15.0 m from the right pier. What upward support force does the right pier provide?
a. 40.6 kN b. 51.3 kN
c. 25.6 kN d. 44.4 kN
e. 42.5 kN
[Ques. 8] Anika and Sam are astronauts floating in space outside their spaceship. They are tethered together by a rope of length 10.5 m. They both begin pulling on the rope at the same time. Anika has mass of 80 kg, and Sam 100 kg. Because her mass is less, Anika reaches the middle of the rope first. Assuming the center of the rope is at the origin and that Anika and Sam start at 5.25 m and 5.25 m, respectively, where is Sam when Anika reaches the middle?
a. 1.05 m
b. 0.53 m
c. 9.45 m
d. 4.20 m
[Ques. 9] A double satellite is launched into space. It consists of a satellite of mass m and another satellite of mass 5m. The connecting mechanism of these satellites is an explosive bolt and a compressed spring, both of negligible mass. The bolt is exploded and the satellites drift apart having been pushed by the spring. When the less massive satellite has moved a distance of 2.5 m from the center of mass of the double satellite, how far away from it is the satellite of greater mass?
a. 3.0 m b. 2.0 m
c. 0.50 m d. 4.5 m
[Ques. 10] Three masses are positioned along the x-axis. Their masses and positions are m1 = m with x1 = 1.0 m, m2 = 2m with x2 = 2.0 m, and m3 = 9.0m with x3 = 3.0 m. What is the x-coordinate of the center of mass of this system, to the nearest tenth?
a. 4.7 m b. 2.7 m
c. 2.0 m d. 0.7 m
e. Not enough information
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