Answer:
A.607m/s | B.1.834Mach (speed of sound)
Explanation:
The plane's speed starts out at 145m/s, meaning after we calculate how many m/s it has accelerated, we must add that to the total.
If it accelerates for 20 seconds at a rate of 23.1m/s^2, this means that it accelerates 23.1m/s/s, or in words it gains 23.1 m/s every second. So, to calculate the gain in speed we simply multiply this by the duration of 20 seconds and get 462 m/s. Now, we add this to 145m/s, and get an end velocity of 607m/s.
For the plane's speed in terms of speed of sound, we divide 607m/s by the speed of sound, or 331m/s, and get ~1.834 Mach(speed of sound)
Answer:
In words, it could be said that the force times the time equals the mass times the change in velocity. In physics, the quantity Force • time is known as impulse. And since the quantity m•v is the momentum, the quantity m•Δv must be the change in momentum. The equation really says that the Impulse = Change in momentum.
The mechanical energy of the girl will be conserved because the system is isolated and the initial potential energy will be equal to final kinetic energy.
<h3>
What is the law of conservation of energy?</h3>
The law of conservation of energy states that energy can neither be created nor destroyed but can be transformed from one form to another.
The change in the potential energy of the launched from a height into the pool without friction from the given height h is calculated by applying the following kinematic equation.
ΔP.E = ΔK.E
where;
- ΔP.E is change in potential energy of the child
- ΔK.E is change in the kinetic energy of the child
mghf - mghi = ¹/₂mv² - ¹/₂mu²
where;
- m is the mass of the girl
- g is acceleration due to gravity
- hi is the initial height of the girl
- hf is the final height when she is launched into the pool
- u is the initial velocity
- v is the final velocity of the girl
Thus, for every closed or isolated system such as this case, mechanical energy is always conserved because the initial potential energy of the girl will be converted into her final kinetic energy.
Learn more about conservation of mechanical energy here: brainly.com/question/332163
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