For the work-energy theorem, the work done by the worker must be equal to the variation of mechanical energy of the bucket.
The variation of mechanical energy of the bucket is sum of the variation of potential energy (U) and kinetic energy (K):
Taking the ground as reference, the variation of potential energy of the bucket is:
while the variation of kinetic energy is simply equal to the final kinetic energy of the bucket, since initially it was at rest (so its initial kinetic energy was zero):
So the minimum amount of work that must be done is equal to the variation of mechanical energy of the bucket:
The force of attraction between 2 charged spheres can be explained by Coulomb's law,
It states the force of attraction is directly proportional to the magnitudes of the charges and inversely proportional to the square of the distance between the charges.
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where F - force of attraction/repulsion
q₁ and q₂ - charges of the 2 spheres
k - Coulomb's law constant
r - distance between the spheres
In the question given, the charges of the spheres remain constant in both instances, only distance changes. Therefore (kq₁q₂) = c which is a constant
then F = c / r²
first instance
6 x 10⁻⁹ N = c/ (20 cm)² ---1)
F = c/(10 cm)² --- 2)
2) / 1)
F = 6 x 10⁻⁹ x 4
F = 2.4 x 10⁻⁸ N
I’m not too sure, but I think the answer is ‘waxing crescent’. I hope it’s right.
Answer:
- The gravitational force by the Earth on the object, and by the object on the Earth is
- = 6.674×10−11 m3⋅kg−1⋅s−2 × 6 × 10^24 kg × 44.5 kg/(6.4 × 10^6 m)²
<u>Please note that the ration between the gravitation force 435 and the mass 44.5</u>
- should be gravitational acceleration
- I attribute the discrepancy between 9.78 and the usual 9.81 to rounding off in the
- Earth's weight and radius.
The mass of the Moon is M / 81.3.
The radius of the Moon is R × 0.27.
The gravitational force on the moon would be
G(M/81.3)m/(R×0.27)² = 0.17×GMm/R²
The gravitational force on the moon is smaller by the factor of about 0.17.
Answer:
The one with the least amount mass
Explanation:
I take a Physics Class