I'm not sure what your question is. But, the half life is the amount of time required for half the material to decay. For U238 this is 4.5 billion years, whilst for Fr-223 (Francium) its about 22 minutes. To calculate the time for something to decay you need to use the equation:
Mass (after time t) = Mass (initial) * (0.5)^(time/half life)
Hope this helps
Answer:
nine times as much.
Explanation:
K.E of A = 9 times K.E of B
Answer:
jwuwhisbuebeu said that good morning and private s the
The atom must have gained 1 or more electrons or must have lost 1 or more electrons.
The situation (heat going through the ceiling) describes
conduction ... heat going from one place to another by
soaking through some material.
A). This is the one. Heat goes from from the marshmallow
to your hand by soaking through the wire. This is conduction too.
B). No. The heat in the room goes from the floor to the ceiling
because the warm air rises and carries it there. This is convection.
C). No. There's nothing for the heat to soak through between
the sun and the roof, and nothing that can move from the sun
to the roof and bring the heat with it. This is radiation.
D). No. Cold water sinks from the surface to the bottom because
warm water rose from the bottom to the surface, taking heat with it.
This is convection.
