CassLovesKinematics
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- Homework Statement
- A helicopter (weight 2.48*10^5 N) has a given position of r = (0.042 m/s^3)t^3*i + (1.9 m/s)t*j - (0.098 m/s^2) t^2 k.
Find the net force of the helicopter at t = 9.5 , express the components of the net force in newtons.
- Relevant Equations
- 1 N = 1kg*m/s^2
F = m*a
I understand that you have to take second derivative of r to find a
Doing it in dr^2/dt^2 = 6(0.042 m/s^3) t*i - 0.196 m/s^2 k, and then multiply (2.48*10^5) to 6(0.042*9.5) and to -0.196
However, my homework platform is NOT accepting 593712 N (or any rounding of it)for i vector and -48608 (or any rounding of it) for k
It INSTEAD insists that the correct answer for i is 6.1*10^4 and K is -5*10^3. Both of these answers are both a whole magnitude off, and that math is wrong. I read that pearson can sometimes get it wrong, but I thought that was years ago. Am I doing something wrong here, I've run it countless times.
Doing it in dr^2/dt^2 = 6(0.042 m/s^3) t*i - 0.196 m/s^2 k, and then multiply (2.48*10^5) to 6(0.042*9.5) and to -0.196
However, my homework platform is NOT accepting 593712 N (or any rounding of it)for i vector and -48608 (or any rounding of it) for k
It INSTEAD insists that the correct answer for i is 6.1*10^4 and K is -5*10^3. Both of these answers are both a whole magnitude off, and that math is wrong. I read that pearson can sometimes get it wrong, but I thought that was years ago. Am I doing something wrong here, I've run it countless times.