Calculate the torque (magnitude and direction) about point O due to the force F

Question

Calculate the torque (magnitude and direction) about point O due to the force F in each of the cases sketched in the figure (Figure 1) . In each case, the force F and the rod both lie in the plane of the page, the rod has length 4.00 m, and the force has magnitude 13.0 N .

Part A

Calculate the magnitude of the torque in case (a).

Part B

Find the direction of the torque in case (a).

Part C

Calculate the magnitude of the torque in case (b)

Part D

Find the direction of the torque in case (b).

Part E

Calculate the magnitude of the torque in case (c)

Part F

Find the direction of the torque in case (c).

Part G

Calculate the magnitude of the torque in case (d)

Part H

Find the direction of the torque in case (d).

Find the direction of the torque in case (d).

Part I

Calculate the magnitude of the torque in case (e)

Part J

Find the direction of the torque in case (e).

Part K

Calculate the magnitude of the torque in case (f)

Part L

Find the direction of the torque in case (f).

Find the direction of the torque in case (f).

of 1

Calculate the torque (magnitude and direction) about point O due to the force F in each of the cases sketched in the figure (Figure 1) . In each case, the force F and the rod both lie in the plane of the page, the rod has length 4.00 m, and the force has magnitude 13.0 N .

Part A

Calculate the magnitude of the torque in case (a).

Explanation / Answer

Torque is given by the vector cross product: T = F X r
In all cases, the force has a magnitude of 13.0N and the rod has a length of 4.00m.

A) and B) T = F X r = 13 * 4 * sin(90°) = 52 Nm
Direction, by right hand rule, is perpendicular to the page, coming toward the viewer.

C) and D) T = F X r = 13 * 4 * sin(120°) = 45.03 Nm
Same direction.

E) and F) T = F X r = 13 * 4 * sin(30°) = 26 Nm
Same direction.

G) and H) T = 13 * (4 - 2) * sin(-60°) = -22.52 Nm
Since I used a negative angle, I can consider the resultant vector pointing in the same direction, only a negative magnitude. The torque is directed away from the viewer.

I) and J) The distance vector r is zero, so T = 0

K) and L) The angle between the force and point O is zero, so T = 0

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.