Answer:
m = 0.217 kg
Explanation:
We can solve this exercise using the conservation of angular momentum. For this the system is formed by the bar and the disk, so that the forces during the crash have been internal and the angular momentum is preserved
initial angular mount. Before impact
L₀ = L_bar + L_ disk
L₀ = I_bar w₀ + m r v₀
final angular momentum. Right after the crash
= I_bar wf = m r v_{f}
The moment of inertia of a bar that rotates at its ends is
I_bar = 1/12 M L
how the angular momentum is conserved
L₀ = L_{f}
I_barr w₀ + mr v₀ = I_barr w_{f} + m r v_{f}
I_bar (w₀- w_{f}) = m r (v₀- v_{f})) r
m = I_bar (w₀ - w_{f}) / r (v₀ -v_{f})
m = 1/12 M L (w₀ -w_{f} ) / r (v₀ -v_{f})
in the exercise it indicates that the initial speed of the disc is v₀ = 20 m / s and its final speed is v_{f} = -16 m / s, the negative sign is because the disc recoils
we calculate
m = 1/12 35 0.90 (0 + 1.14) / [0.30 (30- (-16))]
m = 0.217 kg
Answer:
when the ball is at its highest in the air.
Explanation:
I don't know for sure, but when the ball is in the air it has potential energy to fall(or something like that).
Answer:
glass if for a good view, but for absorbing heat concrete and brick is the best
Explanation:
wood is not a good idea bc it can cause fires from too much heat and it absorbs less heat but all of that depends on how good the material your using