Say my vehicle currently in orbit had large wings that would provide the necessary lift, would it be possible to bleed off the energy so slowly and gradually lose altitude that no heat shield would be required? I was thinking that even at the low pressure at high altitude, the wings along with th...

According to general relativity planets and the sun bend the spacetime, and that is the explanation of gravity. However, does this hold true for smaller objects, like toys, pens, etc.? Do they also bend spacetime?

To my knowledge, momentum is conserved when net external force equals zero. In the case of a block $m_1$ attached to a string hitting another block $m_2$, there must be a net force on $m_1$, which would be its centripetal force, pointing inward. Therefore comparing just before $m_1$ hits $m_2$ an...