Answer:
Which of the following was not a reaction to John Brown's execution because of his failed raid on Harper's Ferry ???????
Explanation:
I think that the solar panel would work under a fluorescent or halogen light if the photons are being produced. These types of lights mimic sunlight so it would not work as good as the real thing but it could work. Just not be as powerful.
A
The horizontal force cancels out. The two 4Ns go in opposite directions. So they don't affect the outcome.
The Vertical force is 6N up - 2 N down = 4 N Up
Answer 4 N up
B
The horizontal and vertical forces cancel out. Each gives 3N - 3N =0
The net force is 0
C
You only have horizontal forces on this one
5N - 3N = 2N
The answer is 2N to the right.
Answer:
b. Increasing the mass of the arrow.
Explanation:
The formula is K=1/2mv^2. Increasing the mass also increases the kinetic energy.
Answer:
It's only 1.11 m/s2 weaker at 400 km above surface of Earth
Explanation:
Let Earth radius be 6371 km, or 6371000 m. At 400km above the Earth surface would be 6371 + 400 = 6771 km, or 6771000 m
We can use Newton's gravitational law to calculate difference in gravitational acceleration between point A (Earth surface) and point B (400km above Earth surface):

where G is the gravitational constant, M is the mass of Earth and r is the distance form the center of Earth to the object





So the gravitational acceleration at 400km above surface is only 0.885 the gravitational energy at the surface, or 0.885*9.81 = 8.7 m/s2, a difference of (9.81 - 8.7) = 1.11 m/s2.