Answer:
because the book's is covered by papers
Answer:
a)
= 4.67m/s
b) V = 8.29 m/s
Explanation:
Givens:
The bullet is 5.30g moving at 963m/s and its speed reduced to 426m/s. The wooden block is 610g.
a) From conservation of linear momentum
Pi = Pf

where
are the mass and the initial velocity of the bullet,
and
are the mass and the initial velocity of the wooden block, and
and
are the final velocities of the wooden block and the bullet
The wooden block is initial at rest
this yields

By solving for
adn substitute the givens
= 
= 
= 4.67m/s
b) The center of mass speed is defined as

substituting:

V = 8.29 m/s
Is a physical change because only the state of the matter has changed.
Physical changes can often be reversed. Allowing the water to evaporate will return the salt to a solid state.
It has not combined with the water to cause an irreversible chemical reaction.
Answer:
I believe it's sound energy.
Explanation:
Sound can move through air, whereas electric and radiant energy don't have to.