Answer:
Option b, pothographs from drones.
Explanation:
the USGS (U.S. Geological Survey) decided to make photographic captures from drones to the volcanic surfaces, which allowed through observations to understand things like the characteristics of the lava, the height of the volcanic plumes (among others).
Podemos ver en el siguiente enlace un ejemplo de fotografía tomada desde un dron al Kilauea.
https://www.usgs.gov/media/images/k-lauea-volcano-drone-over-lava-channel
The strength of the gravitational field is given by:
where
G is the gravitational constant
M is the Earth's mass
r is the distance measured from the centre of the planet.
In our problem, we are located at 300 km above the surface. Since the Earth radius is R=6370 km, the distance from the Earth's center is:
And now we can use the previous equation to calculate the field strength at that altitude:
And we can see this value is a bit less than the gravitational strength at the surface, which is
.
Let the mass of the person be m. Total momentum is conserved (because the exterior forces on the system are balanced), especially the component in the vertical direction.
Given that,
Mass of gallon is M
Let man mass be m
Velocity of man is v
Let velocity if ballot be Vb
When the person begin to move we have
Conservation of momentum
mv + MVb=0
MVb=-mv
Vb= -(m/M) v
Given that the mass of man is less than mass of balloon. i.e. m<M
So, if m<M, then, m/M <1
Therefore, .
Vb= -(m/M) v
Vb< -v
This implies that the velocity of balloon is less than the velocity of man and if is also moving in opposite direction
So the man is moving upward, then the balloon is moving downward and it's velocity is less than the velocity of man,
The answer is C
Down with a speed less than v
Answer:
Studies show that eating fewer animal-based products could reduce water use since animal production uses more water than crops do. In addition, reducing the amount of food that's lost or wasted at various points in the food supply chain could feed about 1 billion extra people while simultaneously reducing water use.
Answer:
15 m/s or 1500 cm/s
Explanation:
Given that
Speed of the shoulder, v(h) = 75 cm/s = 0.75 m/s
Distance moved during the hook, d(h) = 5 cm = 0.05 m
Distance moved by the fist, d(f) = 100 cm = 1 m
Average speed of the fist during the hook, v(f) = ? cm/s = m/s
This can be solved by a very simple relation.
d(f) / d(h) = v(f) / v(h)
v(f) = [d(f) * v(h)] / d(h)
v(f) = (1 * 0.75) / 0.05
v(f) = 0.75 / 0.05
v(f) = 15 m/s
Therefore, the average speed of the fist during the hook is 15 m/s or 1500 cm/s
