Answer:
i) 24.5 m/s
ii) 30,656 m
iii) 89,344 m
Explanation:
Desde una altura de 120 m se deja caer un cuerpo. Calcule a 2.5 s i) la velocidad que toma; ii) cuánto ha disminuido; iii) cuánto queda por hacer
i) Los parámetros dados son;
Altura inicial, s = 120 m
El tiempo en caída libre = 2.5 s
De la ecuación de caída libre, tenemos;
v = u + gt
Dónde:
u = Velocidad inicial = 0 m / s
g = Aceleración debida a la gravedad = 9.81 m / s²
t = Tiempo de caída libre = 2.5 s
Por lo tanto;
v = 0 + 9.8 × 2.5 = 24.5 m / s
ii) El nivel que el cuerpo ha alcanzado en 2.5 segundos está dado por la relación
s = u · t + 1/2 · g · t²
= 0 × 2.5 + 1/2 × 9.81 × 2.5² = 30.656 m
iii) La altura restante = 120 - 30.656 = 89.344 m.
Answer:
proof in explanation
Explanation:
First, we will calculate the number of half-lives:
where,
n = no. of half-lives = ?
t = total time passed = 2100 million years
= half-life = 700 million years
Therefore,
Now, we will calculate the number of uranium nuclei left (
):
and the rest of the uranium nuclei will become thorium nuclei (
)
dividing both:
<u>Hence, it is proven that after 2100 million years there are seven times more thorium nuclei than uranium nuclei in the rock.</u>
Answer: The period of the pendulum will increase. Because of less gravity
Explanation:
Since the force of gravity is less on the Moon, the pendulum would swing slower at the same length and angle and its frequency would be less. Hence more time period will be experienced by the pendulum. On the moon, the acceleration due to gravity g is less when compared to that of the earth.
I think that the wavelengths of an incoming solar radiation are shorter than the wavelengths of reradiated heat. This is because the incoming solar radiation to the surface of the earth is in the utraviolet (short) to near infrared (long) wavelength bands. After absorption has taken place, surfaces reradiate heat energy back to the atmosphere at long wavelength infrared.
