Is conservation of energy the same as conservation of momentum?

Conservation of Energy: the total energy of the system is constant. Conservation of Momentum: the mass times the velocity of the center of mass is constant.

Why is it difficult to use the law of conservation of energy to calculate the effects of a collision?

Inelastic collisions do lose energy to heat and vibration. Inelastic collisions actually do conserve energy, but the loss of energy to heat and mechanical vibration is hard to calculate so the math equating energy before and energy after is hard to balance.

When can we not use conservation of momentum?

Conservation of momentum is violated only when the net external force is not zero. But another larger system can always be considered in which momentum is conserved by simply including the source of the external force.

Why do we use conservation of energy?

As objects move around over time, the energy associated with them—e.g., kinetic, gravitational potential, heat—might change forms, but if energy is conserved, then the total will remain the same. Conservation of energy applies only to isolated systems.

During which type of collision is none of the energy converted to sound energy?

During which type of collision is none of the energy converted to sound energy? In an elastic collision, both momentum and kinetic energy are conserved. Almost no energy is lost to sound, heat, or deformation.

During which type of collision do the two objects stick together?

Inelastic collision
Key terms

Term (symbol)	Meaning
Inelastic collision	Collision which conserves momentum but not kinetic energy.
Totally inelastic collision	Collision where the objects stick together and have the same final velocity. Also called a perfectly inelastic collision.

How can we solve conservation of energy?

The conservation of energy formula goes Ki+Ui=Kf+Uf. U is potential energy and K is kinetic energy.