Plaease help me answer all of these questions. I do not think I am doing it righ
ID: 1608992 • Letter: P
Question
Plaease help me answer all of these questions. I do not think I am doing it right. Thank you!!
Questions 4 7 refer to the situation illustrated in the figure below Two masses are attached to a weightless rod with a supporting pivot (or fulcrum) positioned somewhere on the rod. Assume each square is 1.0 cm in length. Assume that a force is one that is directed upwards 300.0 m B. C D E 3.0 kg 1.0 kg n order for the system to be in equilibrium in terms of forces, the supporting pivot (or fulcrum) must provide a force equal to a) 4.0 kg b. 2.0 kg c. -39.2 N d. -19.6 N e. 19.6 N f. +39.2 N 5. Where should the supporting pivot be located on the rod to produce the largest net torque? Hint: If there is a net torque, the net torque is not equal to zero a. A b. B c. C d. D e. E 6. Where should the supporting pivot be located on the rod to produce the largest net torque? Hint: If there is a net torque, the net torque is not equal to zero a. A b. B c. C d. D e. E 7. Where should the supporting pivot be located on the rad to produce no rotation? a. A c. C e. E b. B d. D Questions 8 10 refer to a CD that slows down from 635 revolutions per minute (rpm's) counterclockwise to zero in 4.5 seconds 8. What is the direction of the angular velocity during this time? c. 0 9. What is the direction of the angular acceleration during this time? 10. What is the angular acceleration of the disk during this time? a. 3810 rad/s b. 890 rad/s c. 66 rad/s d. 141 rad/s e. 24 rad/s f, 15 rad/s 11 A sculpture consists of 4 solid spheres of different masses (3.6 kg, 2.8 kg, 1.8 kg, and 1.4 kg) attached by 3 massless rods with different lengths as shown. The diagram provide below is not drawn to each sphere and the lengths of the rods provided were Assume the rods were inserted in Scale measured from the centers of each sphere 4 kg a. The center of mass of the sculpture is greater than the center 8 kg. of gravity of the sculpture b. The center of mass of the sculpture is located near a position that is above the center of the sculpture 75 cm 55 cm c. The center of mass of the sculpture is located on the left and below the center of the sculpture d. If the solid spheres were switched to different positions on the sculpture, the center of mass of the sculpture would remain at the 3.6 kg: 2.8 kg same position e. The center of mass of an object is located in the 2.8 kg sphere f. The center of mass of the sculpture is located in the center of the 85 c sculptureExplanation / Answer
4) f) +39.2 N
net force on the system must be equl to zero.
Fnety = 0
F_flucrum - m*g - M*g = 0
F_fulcrum = (m + M)*g
= (1 + 3)*9.8
= 39.2 N
5) a) A
6) e)E
7) b) B
8) a) +
9) b) -
10) f) 15 rad/s^2
wi = 635 rev/min = 635*2*pi/60 = 66.5 rad/s
wf = 0
angular acceleration, alfa = (wf - wi)/t
= (0 - 66.5)/4.5
= -14.8 rad/s^2
= -15 rads^2