Answer:
In the more scientific viewpoint, the most important thing that she must do is caring for her hygiene and put some plastic gloves in her hands.
This is because there are lots of particles that can be retained in the hands (dust, skin, etc), and when examining the scene, she may drop some of these particles, "contaminating" the scene in this way with information that only will affect the investigation.
So the most important thing is being prepared to not affect anything in the crime scene
Given:
speed of passing pony 5 m/s
frequency of the sound produced: 221 Hz
speed of sound 342 m/s
Let us use the Doppler Shift Formula:
Where the <span>source is moving away from the observer at rest
</span>
f' = (v / v+vs) f
Where, vs<span> = Velocity of the Source,</span>
v = Velocity of sound or light in medium,
f = Real frequency,
f' = Apparent frequency.
f'= [342 m/s / (342 m/s+5m/s)] * 221 Hz
f' = 0.9856 * 221Hz
f' = 217.8176 Hz or 218 Hz
The observed frequency <span>of the hooves after the pony has passed your position is 218 Hz.</span>
Explanation:
Pressure = force / area
P = (68 kg × 9.8 m/s²) / (2 × (0.04 m)²)
P = 208,250 Pa
Converting to psi:
P = 208,250 N/m² × (0.225 lbf/N) × (0.0254 m/in)²
P = 30.2 psi
B. When the ball is rolling across the floor at a constant velocity, the change in its kinetic energy is zero.
<h3>
What is change in kinetic energy?</h3>
The change in kinetic energy of an object is the dereference between the final kinetic energy and the initial kinetic energy.
ΔK.E = K.Ef - K.Ei
ΔK.E = 0.5m(vf² - vi²)
where;
- K.Ef is the final kinetic energy
- K.Ei is the initial kinetic energy
- vf is final velocity
- vi is initial velocity
At constant velocity, the initial velocity and final velocity are equal.
ΔK.E = 0.5m(0) = 0
Thus, when the ball is rolling across the floor at a constant velocity, the change in its kinetic energy is zero.
Learn more about kinetic energy here: brainly.com/question/25959744
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