# Search results

1. ### Acceleration from min/max derivatives

Homework Statement x(t) = -0.01t^3 + t^2 - 20t + 4 Homework Equations Min is when t = 12.3 Max is when t = 54.4 The Attempt at a Solution I got -0.03t^2 + 2t - 20 as the derivative. I substituted in t = 12.3 and 54.4 and got 0.02 and 0.19 which don't seem right at all. Because...
2. ### Rocket Height

Homework Statement A rocket, initially at rest on the ground, accelerates straight upward from rest with constant acceleration 53.9 m/s^2. The acceleration period lasts for time 7.00 s until the fuel is exhausted. After that, the rocket is in free fall. Find the maximum height ymax reached by...
3. ### Adding Scalar Multiples of Vectors Graphically

Homework Statement Draw the vector C = 1.5A -3B (Mastering Physics problem) A is 4.5 and B is 1.0 The Attempt at a Solution I've tried it 4 times and still can't do it. I've looked at some sites but I guess I just don't understand it. I've heard of the head to tail method, or something...