From the question, The kinetic energy of the fired arrow is equal to the work done by the bale of hale in stopping the arrow.
We make use of the following formula
mv²/2 = F'd................... Equation 1
Where
- m = mass of the arrow
- v = velocity of the arrow
- F' = average stopping force acting on the arrow
- d = distance of penetration
Make F' the subject of the equation
F' = mv²/2d.................. Equation 2
From the question,
Given:
- m = 20 g = 0.02 kg
- v = 60 m/s
- d = 40 cm = 0.4 m
Substitute these values into equation 2
Hence, The average stopping force acting on the arrow is 90 N
Learn more about average stooping force here: brainly.com/question/13370981
(1.a) The surface area being vibrated by the time the sound reaches the listener is 5,026.55 m².
(1.b) The intensity of the sound wave as it reaches the person listening is 0.02 W/m².
(1.c) The relative intensity of the sound as heard by the listener is 103 dB.
(2.a) The speed of sound if the air temperature is 15⁰C is 340.3 m/s.
(2.b) The frequency of the sound heard by the suspect is 614.3 Hz.
<h3>
Surface area being vibrated</h3>
The surface area being vibrated by the time the sound reaches the listener is calculated as follows;
A = 4πr²
A = 4π x (20)²
A = 5,026.55 m²
<h3>Intensity of the sound</h3>
The intensity of the sound is calculated as follows;
I = P/A
I = (100) / (5,026.55)
I = 0.02 W/m²
<h3>Relative intensity of the sound</h3>
<h3>Speed of sound at the given temperature</h3>
<h3>Frequency of the sound</h3>
The frequency of the sound heard is determined by applying Doppler effect.
where;
- -v₀ is velocity of the observer moving away from the source
- -vs is the velocity of the source moving towards the observer
- fs is the source frequency
- fo is the observed frequency
- v is speed of sound
Learn more about intensity of sound here: brainly.com/question/17062836
Answer:
5 m/s, moving to the South.
Explanation:
Parameters given:
Mass of car, m = 1500 kg
Initial velocity of car, u = 15 m/s
Mass of truck, M = 4500 kg
Initial velocity of truck, v = 0 m/s (Truck is at rest)
Final velocity of car, U = 0 m/s (Car comes to a stop)
Final velocity of truck = V
Because the collision is elastic, we can apply the principle of conservation of momentum, we have that:
Total initial momentum = Total final momentum
m*u + M*U = m*v + M*V
(1500 * 15) + (4500 * 0) = (1500 * 0) + (4500 * V)
22500 + 0 = 0 + 00V
=> V = 22500/4500
V = 5 m/s
The velocity carries a positive sign, hence, it's moving in the same direction as the car was moving initially.
That is, it's moving to the South.
40 seconds I’m pretty sure sorry if I’m wrong
