Work, Energy, and Power in Physics
What happens to total mechanical-energy when air resistance acts on a falling parachuter descending with constant velocity?
Decrease-in-kinetic-and-gravitational-potential-energy-as-lost-to-air-resistance
Increase-in-gravitational-potential-energy-as-falling-object-slows-down
No change occurs in total mechanical-energy as gravitational-potential converts entirely into thermal-energy-due-to-air-resistance
Kinetic-energy-is-transferred-to-the-surrounding-air-particles-increasing-their-mechanical-energy
What is impossible to calculate using a conservation energy principle, if the body in question is undergoing simple harmonic oscillations?
Gravitational potential energy at a particular point
Total mechanical energy at the start of the oscillation cycle
Kinetic energy at a turning point
Potential energy stored in the oscillating spring
In a closed system where two billiard balls collide elastically, how might quantum mechanical principles indirectly influence the conservation of kinetic energy on a macroscopic scale?
Quantum tunneling increases the effective collision cross-section.
Heisenberg’s uncertainty principle predicts variable post-collision velocities.
Photon emission during collisions slightly reduces system kinetic energy.
Microscopic variations in surface structure may alter collision characteristics.
In a perfectly elastic collision scenario of two objects of mass and with initially stationary, what is the ratio of final speed to the final speed after said collision?
A ball rolls up a hill without friction; at what point will its kinetic and potential energies be equal?
At no point; only total mechanical energy remains constant.
Halfway up the hill.
When its speed is reduced by half from that at the bottom.
At the top of the hill where it comes to rest for an instant.
A rotating solid disk experiences angular deceleration due to magnetic braking; what effect arises from combining Maxwell's laws with Newtonian mechanics?
Electromagnetic eddy currents opposing rotation manifest additional torque resisting motion.
Spin-orbit coupling aligns magnetic dipoles decreasing net magnetization resultant loss rates.
Magnetic fields penetrate reducing rotational inertia modifying angular velocity proportionately.
Lorentz forces induce charge separation shifting center mass adjusting precession dynamics accordingly.
A ball attached to a string swings from point A (the highest point) through point B (the lowest point) and up to point C at an equal height as A; if air resistance is negligible but not zero, how does its velocity at point B compare with that predicted by an ideal scenario where no external forces act?
Much less than predicted because all initial potential energy is lost to air resistance.
Slightly less than predicted by conservation of energy without air resistance.
Greater than predicted due to additional force provided by air resistance.
Exactly the same as predicted by conservation of energy without air resistance.

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If a pendulum with length swings from an initial angle with negligible air resistance, what approximation can affect calculating its period most significantly?
Neglecting Earth's rotation effect on pendulum motion for moderate latitudes
Considering string mass in tension calculations when it's negligible
Assuming simple harmonic motion for large
Ignoring variation in with altitude for pendulums on tall buildings
If two identical masses attached to springs with different constants and displaced by the same amount from equilibrium points, will they have equal kinetic energies when they reach the equilibrium point?
Yes, but only if the springs are compressed instead of extended.
No, kinetic energy is only dependent on the mass and displacement, not the stiffness of the spring.
Yes, the displacement is both the same and the masses are identical, so their kinetic energies should be equal.
No, the mass attached to the stiffer spring will have less kinetic energy because the force required to compress it is greater.
If two objects collide in a perfectly inelastic collision, which quantity is conserved?
Velocity of each object
Momentum of the system
Kinetic energy of each object
Potential energy of the system