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2 years ago

9

Archerfish are tropical fish that hunt by shooting drops of water from their mouths at insects above the waterÂs surface to knoc

k them into the water, where the fish can eat them. a 65-g fish at rest just at the surface of the water can expel a 0.30-g drop of water in a short burst of 5.0 ms. high-speed measurements show that the water has a speed of 2.5 m/s just after the archerfish expels it.

2 answers:

sergij07 [2.7K]2 years ago

3 0

Answer:

.012

Explanation:

Take the mass of the fish and divide it by the mass of the water:

65/.30=216.667

Divide the given speed by the value we found above:

2.5/216.667=.0115

Answer can be rounded up to .012

Schach [20]2 years ago

3 0

The speed of the archerfish immediately after it expels the drop of water is about (b) 0.012 m/s

$\texttt{ }$

<h3>Further explanation</h3>

Newton's second law of motion states that the resultant force applied to an object is directly proportional to the mass and acceleration of the object.

$\large {\boxed {F = ma }$

F = Force ( Newton )

m = Object's Mass ( kg )

a = Acceleration ( m )

Let us now tackle the problem !

$\texttt{ }$

<em><u>The Question:</u></em>

<em>What is the speed of the archerfish immediately after it expels the drop of water? </em>

<em>(a) 0.0025 m/s; </em><em>(b) 0.012 m/s</em><em>; (c) 0.75 m/s; (d) 2.5 m/s.</em>

<u>Given:</u>

mass of fish = m₁ = 65 g

mass of drop of water = m₂ = 0.30 g

speed of water = v₂ = 2.5 m/s

initial speed of water = initial speed of archerfish = u₁ = u₂ = 0 m/s

<u>Asked:</u>

the speed of the archerfish = v₁ = ?

<u>Solution:</u>

<em>We will use </em><em>Conservation of Momentum Law </em><em>as follows:</em>

$m_1u_1 + m_2u_2 = m_1v_1 + m_2v_2$

$65(0) + 0.30(0) = 65v_1 + 0.30(2.5)$

$0 + 0 = 65v_1 + 0.75$

$65v_1 = -0.75$

$v_1 = -0.75 \div 65$

$\boxed{v_1 \approx -0.012 \texttt{ m/s}}$

$\texttt{ }$

<h3>Conclusion :</h3>

<em>The speed of the archerfish immediately after it expels the drop of water is about </em><em>0.012 m/s</em>

$\texttt{ }$

<h3>Learn more</h3>

Impacts of Gravity : brainly.com/question/5330244
Effect of Earth’s Gravity on Objects : brainly.com/question/8844454
The Acceleration Due To Gravity : brainly.com/question/4189441
Newton's Law of Motion: brainly.com/question/10431582
Example of Newton's Law: brainly.com/question/498822

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<h3>Answer details</h3>

Grade: High School

Subject: Physics

Chapter: Dynamics

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