A small repair drone of mass drifts near a disabled satellite

PHYSICS · Multi-part · AP · Physics 1: Algebra-based · Kinematics · Kinematics

Problem

A small repair drone of mass 6.0 kg6.0\,\text{kg} drifts near a disabled satellite. Two identical cold-gas thrusters mounted orthogonally on the drone can fire in the +x+x and +y+y directions, respectively. A sequence of computer-controlled pulses is executed while on-board sensors record data. Piecewise description of the net external force components on the drone (SI units): Interval I: 0≤t<1.5 s0\le t<1.5\,\text{s} • Fx=+9.0 NF_{x}=+9.0\,\text{N} • Fy=+12.0 NF_{y}=+12.0\,\text{N} Interval II: 1.5 s≤t<3.0 s1.5\,\text{s}\le t<3.0\,\text{s} • Fx=0 NF_{x}=0\,\text{N} • Fy=+12.0 NF_{y}=+12.0\,\text{N} Interval III: 3.0 s≤t<4.0 s3.0\,\text{s}\le t<4.0\,\text{s} • Fx=−9.0 NF_{x}=-9.0\,\text{N} (opposite the +x+x direction) • Fy=0 NF_{y}=0\,\text{N} Interval IV: t≥4.0 st\ge 4.0\,\text{s} • Fx=0 NF_{x}=0\,\text{N} • Fy=0 NF_{y}=0\,\text{N} At t=0t=0 the drone is momentarily at rest at the origin of an inertial coordinate system: r0=0\mathbf r_{0}=0 and v0=0\mathbf v_{0}=0. Neglect gravitational and other external influences. (a) For each interval, calculate the drone’s acceleration components axa_{x} and aya_{y}. (b) Determine the drone’s velocity components immediately after the end of each interval (at t=1.5 st=1.5\,\text{s}, t=3.0 st=3.0\,\text{s}, and t=4.0 st=4.0\,\text{s}). (c) Compute the drone’s position vector at t=4.0 st=4.0\,\text{s}. (d) Describe the drone’s motion for t>4.0 st>4.0\,\text{s}, and explain how your answer illustrates Newton’s first law and the concept of dimensional independence. (e) Suppose an unexpected micro-meteorite strike at t=5.0 st=5.0\,\text{s} delivers an impulse purely in the +y+y direction. Without performing additional calculations, predict qualitatively how the xx and yy components of the drone’s velocity will be affected and justify your reasoning.

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