Recent content by mingyz0403

This is what I have done so far. Everything seems correct When X<6. When X>6, the calculation is wrong.The Shear force should be 30 kips. However, in Excel it was 48 kips.Could anyone tell what is wrong with my equation? Many thanks for your help.

I had found the singuarity function for the shear and moment. I have a hard time calculating the singuarity function and graphing it using excel. Can anyone explain how to calculate singuarity function and graphing it using excel? Many thanks for your help

Ok, Thank you.

Since there is no friction, there is no radial force acting on Ball B after the pin is remove. Therefore the radial acceleration of Ball B is zero. I don't know how to determine the transverse components of the acceleration of Ball B. I looked at the textbook solution. It takes moment about the...

The soultion used polar corrdinates. Acceleration in polar corrdinates have radial and transeverse components.When calculating the acceleration of collar respect to the rod, the solution only calculates the radial component of acceleration. Is it because the collar is on the rod, so the...

How do you set the direction for this problem? Do you look at the motion of the block? If you set right positive, does that automatically makes upward motion positive? I set right as positive and up as positive for this problem. However, my answer was wrong. Textbook solution set right as...

The correct angle is 28.1 degree.I understand ∅=arctan(m). Isn’t R should be angled ∅ degree away from the normal force.

I know that moment is distance vector x force vector x the degree between them. I understand it uses the moment about A to solve for the unknown force R. I don’t understand why it use Rx1.2m and why the perpendicular distance between A and R is 1.2m. could anyone please explain why? Many...

My answer was correct, however my direction was different from the textbook. I have checked my work a few times ,but not able to find out what I did wrong. Could anyone tell me what I did wrong. Thank you in advance for your help.

This is the FBD I drew

Since the question only asked for one member, I was trying to solve it using method of section. I cut in the middle of BD. I was unable to solve it because it has 4 unknown. Then I looked at the solution, it say that CD is zero force member. I don’t understand why CD is zero force member. Could...

I reslove Ma and Mb into y and z component. Ma=1200sin(20)j+1200cos(20)k Mb=900sin(20)j+1200cos(20)k Mc=-840i I looked at the solution and it states that the y component of Ma is negative (-1200sin(20)j+1200cos(20)k). I understand that Mc is -840i because it is Clockwise. How do you determine...