Because although they cannot see it, they can see it's influence on objects that can be seen, and it's effects.
We know the formulas for momentum and energy. But they both involve the mass of
the object, and we don't know the mass of the baseball. What can we do ?
It's not a catastrophe. The question only asks which one is bigger. If we're clever,
we can answer that without ever knowing how much the momentum or the energy
actually is. We know that both baseballs have the same mass, so let's just call it
' M ' and not worry about what it really is.
<u>Momentum of anything = (mass) x (speed)</u>
Momentum of the first baseball = (M) x (4 m/s) = 4M
Momentum of the second one = (M) x (16 m/s) = 16M
The second baseball has 4 times as much momentum as the first one has.
<u>Kinetic energy of anything = 1/2 (mass) x (speed squared)</u>
KE of the first baseball = 1/2 (M) x (4 squared) = 8M
KE of the second one = 1/2 (M) x (16 squared) = 128M
The second baseball has 16 times as much kinetic energy as the first one has.
Let V = the volume of the balloon
Force of gravity = V * ?hot * g downward
Buoyant force = V * ?cool * g upward
Net upward force F = V * ?cool * g - V * ?hot * g
F = V g (?cool - ?hot)
Mass of the balloon m = V ?hot
a = F/m = V g (?cool - ?hot)/(V ?hot)
a = g(?cool/?hot - 1)
a = 9.8(1.29/0.93 - 1)
a = 3.79 m/s^2
<span>Answer is 3.79 m/s^2</span>
D. chemical to electrical to sound and electromagnetic
Answer:
Toasting in a toaster is usually considered by (infra red) radiation. But the hot coils touch the toast so an element of heating by conduction occurs as well.
Explanation: