Answer:
the anwser is d
Explanation:
you must have a north and south pole
The kinetic energy (KE) of a 0.155 kg arrow that is shot from ground level, upward at 31.4 m/s, when it is 30.0 m above the ground is 30.85 J
Assuming air friction is negligible,
a = - 9.8 m / s²
u = 31.4 m / s
s = 30 m
v² = u² + 2 a s
v² = 31.4² + ( 2 * - 9.8 * 30 )
v² = 985.96 - 588
v² = 397.96 m / s
KE = 1 / 2 m v²
KE = 1 / 2 * 0.155 * 397.96
KE = 0.0775 * 397.96
KE = 30.85 J
Therefore, the kinetic energy ( KE ) when it is 30.0 m above the ground is 30.85 J
To know more about kinetic energy
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Answer:
Sand
Explanation:
While the term buoyancy may confuse the reader, the question here is referring to buoyant force.
Buoyant force is the amount of pressure exerted on an object by the liquid it is in. Given by the formula
Where
= Buoyant Force
= Volume of Object submerged in the liquid
= Density of Liquid
= Force of gravity
Since in this question the swimmer with the sand is completely submerged in water, more of the volume of his preserver is under the water hence the buoyant force is greater on it than the swimmer with the Styrofoam (as part of him is not submerged in water)
Answer:
6.8%
Explanation:
According to Stefan-Boltzmann law, radiation is directly proportional with temperature raised to the fourth power:
P ∝ T⁴
Writing a proportion:
P₁ / P₂ = T₁⁴ / T₂⁴
1.3P / P = (T₁ / T₂)⁴
T₁ / T₂ = ∜1.3
T₁ = 1.068 T₂
The temperature increased by 6.8%.
