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:
2*F
Explanation:
If we put an object of a given size exactly at a distance 2*F from the lens, the virtual image (the image generated by the lens) will be generated at a distance 2*F from the lens and the size will be equal to the size of the real object (but the image will be inverted)
Now let's do the math.
The relation between the distance of the object to the lens O, and the distance between the image and the lens I is:
1/O + 1/I = 1/F
solving for O, we get:
1/O = 1/F - 1/I = (I - F)/(F*I)
O = F*I/(I - F)
Such that the relation between the height of the original object, H and the height of the virtual image H' is:
H/H' = -I/O
Replacing by O we get:
H/H' = -I/(F*I/(I - F))
If the sizes are equal, then H/H' = - 1 (remember that the image is inverted, thus the sign)
-1 = -I/(F*I/(I - F))
F*I/(I - F) = I
F*I = (I - F)*I
F = (I - F)
F + F = I = 2*F
The distance between the image and the lens is 2*F
O = F*I/(I - F) = F*2*F/(2*F - F) = 2*F
The object is at a distance 2*F from the lens.
Queremos crear un diagrama general para calcular el área de un triangulo.
Este será algo como:
- Definir variables
- Pedirle al usuario que introduzca los valores deseados (de las variables).
- Leer los valores deseados y asignarlo a la variable correspondiente.
- Realizar la operación para calcular el área.
- Mostrar en pantalla el resultado.
Como naturalmente habra algunas variaciones segun el programa que utilicemos, lo voy a escribir de forma bastante general.
Primero definamos nuestras variables:
Por ejemple, en fortran usariamos algo como:
real:: B, H, A
Donde B será la variable que usaremos para la base, H para la altura, y A para el área.
Luego tenemos que escribir en pantalla algo que le diga al usario que debe introducir la base y el area.
Luego el programa debe ser capaz de leer ese input.
con algo de la forma:
B = read*input 1
H = read*input 2
Una vez tenemos definidas las variables, simplemente calculamos el área del triangulo:
A = H*B/2
Finalmente la podemos mostrar en pantalla con algo como:
print(A).
Lo que nos mostraría el valor del área.
Concluyendo, el diagrama en general sería:
- Definir variables
- Pedirle al usuario que introduzca los valores deseados (de las variables).
- Leer los valores deseados y asignarlo a la variable correspondiente.
- Realizar la operación para calcular el área.
- Mostrar en pantalla el resultado.
Si quieres aprender más, puedes leer:
brainly.com/question/21949109
Answer:a device for calibrating thermometers at the boiling point of water at a known height above sea level or for estimating height above sea level by finding the temperature at which water boils.
Explanation: