Answer: This is called the Doppler effect, where waves shift frequency and wavelength as the source travels towards you (higher frequency, shorter wavelength) or away from you (lower frequency, longer wavelength)
Explanation:
hoped this helped have a good day :)
The initial horizontal velocity of the rock, in m/s is 21.241 m/s.
<h3>What is projectile?</h3>
When an object is thrown at an angle from the horizontal direction, the object is said to be in projectile motion. The object which follows the projectile motion.
Time taken by the stone to reach the ground is
t = √2h/g
t = √(2x 86)/9.81
t = 4.19s
The horizontal velocity is
V(x) = Horizontal distance traveled / Time taken t
Put the values, we get
V(x) = 89 m/4.19 s
V(x) = 21.241 m/s
Thus, the horizontal velocity is 21.241 m/s
Learn more about projectile.
brainly.com/question/11422992
#SPJ1
<h3>
</h3>
<u>Here Given,</u>
Mass = 100 gram
Change in temperature = -45°C - 15°C => -55°C
Specific heat of glass (c) = 0.800J/g°C
★Heat Energy (Q) = mc∆t
➙ 100g × (-55)°C × 800/1000 J/g°C
➙ 10 × (-55) × 8
➙ -4400 J
★ Hence, Heat Energy is required to cause this change -4400 J = <u>4400J</u>
<u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u>
Answer:
v₁ =√2gh, v₂ = v₁ /√2
Explanation:
Let's use the concepts of energy and work to analyze each case
hill without rubbing. Energy is conserved
starting point. Highest part
Em₀ = U = mg h
final point. Lower part
= K = ½ m v²
Em₀ = Em_{f}
m g h = ½ m v²
v₁ =√2gh
rubbing hill
in this case the energy is not conserved because it is converted into work of the friction force, therefore the variation of the energy is the work of the friction
W = Em_{f} - Em₀
they indicate half of the initial mechanical energy is lost due to friction
W = ½ Em₀
we substitute
- ½ Em₀ = Em_{f} - Em₀
The negative sign is because the friction work always opposes the movement
Em_{f} = ½ Em₀
½ m v₂² = ½ m g h
v₂ = √½ √2gh
v₂ = v₁ /√2
The answer would be C .venus because it goes ( rotates once every 243 days )