What is the Net Force on a Helicopter at 5 Seconds?

AI Thread Summary
To find the net force on the helicopter at t=5.0 seconds, the position vector is given, and the user needs to derive acceleration from this position function. By differentiating the position vector with respect to time, the velocity can be obtained, followed by a second differentiation to find acceleration. The net force can then be calculated using F=ma, where 'm' is the mass of the helicopter. The user expressed confusion over the process and felt they were going in circles without a clear method to find acceleration from the position function. Clarifying the differentiation steps is essential for solving the problem effectively.
xmflea
Messages
43
Reaction score
0
The position of a 2.75x10^5N helicopter under test is given by

r=(0.020m/s^2)t^3i + (2.2m/s)tj - (0.060m/s^2)t^2k

Find the net force of the helicopter at t=5.0s express the vector F in the form Fx, Fy, and Fz

so far i plugged in 5.0 to each component in the r equation which gave me different masses: 2.5, 11.0, and 1.5

then i divided each mass by 5.0 to get velocity, then i plugged everything into the average accleration formula to get different accelerations, and then i finally used F=ma to plug into get different forces for Fx Fy and Fz
.. and it looks like I am just going in a huge circle. not sure how to do this.
 
Physics news on Phys.org
How do you find acceleration when given position as a function of time?
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Trying to understand the logic behind adding vectors with an angle between them'
My initial calculation was to subtract V1 from V2 to show that from the perspective of the second aircraft the first one is -300km/h. So i checked with ChatGPT and it said I cant just subtract them because I have an angle between them. So I dont understand the reasoning of it. Like why should a velocity be dependent on an angle? I was thinking about how it would look like if the planes where parallel to each other, and then how it look like if one is turning away and I dont see it. Since...
Back
Top