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Torque and Angular Momentum Physics System of Particles and Rotational Motion Physics Class 11th

A triangular plate is shown. A force F = 4i - 3j is applied at point P. The torque at point P with respect to point 'O' and 'Q' are :

Option 1 -

15 + 20√3, 15 – 20√3

Option 2 -

-15 - 20√3, 15 – 20√3

Option 3 -

-15 + 20√3, 15 + 20√3

Option 4 -

15 – 20√3, 15 + 20√3

6 Views | Posted a month ago

Asked by Shiksha User

1 Answer

Answered by

Vishal Baghel | Contributor-Level 10

a month ago

Correct Option - 2

Detailed Solution:

Position vector about O (r_o) = 5i + 5√3j

Force vector (F) = 4i - 3j

Torque about O (τ_o) = r_o × F
τ_o = (5i + 5√3j) × (4i - 3j)
τ_o = -15k - 20√3k = (-15 - 20√3)k

Position vector about Q (r_q) = -5i + 5√3j

Torque about Q (τ_q) = r_q × F
τ_q = (-5i + 5√3j) × (4i - 3j)
τ_q = 15k - 20√3k = (15 - 20√3)k

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A triangular plate is shown. A force F = 4i - 3j is applied at point P. The torque at point P with respect to point 'O' and 'Q' are :

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