Answer:
B. 2nmv
Explanation:
Pressure is force over area.
P = F / A
Force is mass times acceleration.
F = ma
Acceleration is change in velocity over change in time.
a = Δv / Δt
Therefore:
F = m Δv / Δt
P = m Δv / (A Δt)
The total mass is nm.
The change in velocity is Δv = v − (-v) = 2v.
A = 1 and Δt = 1.
Plugging in:
P = (nm) (2v) / (1 × 1)
P = 2nmv
Answer: 9.9%
Explanation: efficiency = (work output /work input) × 100
Note that, 1 kilocalorie = 4184 joules, hence 22kcal = 22× 4184 = 92048 joules.
Work output = 9200 j and work input = 92048 j
Efficiency = (9200/92048) × 100 = 0.099 × 100 = 9.9%
<h3>Answer</h3>
At a high temperature above 20° oxygen solubility starts to decrease.
<h3>Explanation</h3>
Oxygen, O2 is a very essential component of water as we can see in its chemical formula h2O.
The solubility of oxygen decreases as temperature increases. This means that warmer water will have less dissolved oxygen than does cooler water.
<h3>Other factors that affects oxygen solubility in water</h3>
Salt levels
higher the salt levels in water, lower will be oxygen in it.
Pressure
Water at lower altitudes can hold more dissolved oxygen than water at higher altitudes because dissolved oxygen will increase as pressure increases.
Answer:

Explanation:
let
be the mass attached, let
be the spring constant and let
be the positive damping constant.
-By Newton's second law:

where
is the displacement from equilibrium position. The equation can be transformed into:
shich is the equation of motion.
The gravitational force exerted by the earth on a person standing on the earth's surface is 602.74 N.
<h3>What is the gravitational force of the earth on the person?</h3>
The gravitational force exerted by the earth on a person standing on the earth's surface is given below as follows:
where
G = 6.67 * 10⁻¹¹
m¹ = 62 kg
m² = 5.97 * 10²⁷ kg
r = 6.4 * 10⁶ m

Therefore, the gravitational force exerted by the earth on a person standing on the earth's surface is 602.74 N.
Learn more about gravitational force at: brainly.com/question/940770
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