An engineer estimates that under the most adverse expectedweather conditions, th
ID: 1722029 • Letter: A
Question
An engineer estimates that under the most adverse expectedweather conditions, the total force on the highway sign in thefigure will be F = ( +-3i - 4j) kN, acting at thecm. The position vector r = (8j + 6k)m. What is the magnitude of the torque this force exerts aboutthe base O? l t l = _____________ m*N (The answer should nothave variables i,j, or k.) I know that you use t = r x F. The answer I get is 24i+- 18j -+24k m*N. This is consistent with the answer in theback of the book. How can I find l t l without using the variables i,j, andk? The multiple signs are also difficult in calculating theanswer. Thank You!!! An engineer estimates that under the most adverse expectedweather conditions, the total force on the highway sign in thefigure will be F = ( +-3i - 4j) kN, acting at thecm. The position vector r = (8j + 6k)m. What is the magnitude of the torque this force exerts aboutthe base O? l t l = _____________ m*N (The answer should nothave variables i,j, or k.) I know that you use t = r x F. The answer I get is 24i+- 18j -+24k m*N. This is consistent with the answer in theback of the book. How can I find l t l without using the variables i,j, andk? The multiple signs are also difficult in calculating theanswer. Thank You!!!Explanation / Answer
An engineer estimates that under the most adverse expectedweather conditions, the total force on the highway sign in thefigure will be F = ( +-3i - 4j) kN, acting at thecm. The position vector r = (8j + 6k)m. What is the magnitude of the torque this force exerts aboutthe base O? l t l = _____________ m*N (The answer should nothave variables i,j, or k.) I know that you use t = r x F. The answer I get is 24i+- 18j -+24k m*N. This is consistent with the answer in theback of the book. How can I find l t l without using the variables i,j, andk? The multiple signs are also difficult in calculating theanswer. Thank You!!!magnitude of torque=242+(-18)2+(24)2=38.41Nm