Lett me come back imma translate this... and then ill come to help
Answer:
The rock will reach 9 m from the ground at eaxactly 5.06 s after it was initially thrown upwards.
Explanation:
We will use the equations of motion for this.
u = initial velocity of the rock = 22 m/s
g = acceleration due to gravity = -9.8 m/s²
y = vertical position of the rock at a time t = 9 m
y₀ = initial height of the rock = 25 m
t = time it takes for the rock to reach height of 9 m.
(y-y₀) = ut + 0.5gt²
(9 - 25) = 22t + 0.5(-9.8)t²
- 14 = 22t - 4.9t²
4.9t² - 22t - 14 = 0
solving this quadratic equation,
t = 5.055 s or - 0.565 s
Since time cannot be negative,
t = 5.055 s = 5.06 s
Hope this Helps!!!
Answer:
Humans use water for many different things. We use water to stay hydrated. Our bodies need water to live. Back in the day people used water for transportation and trading. This was a way to become wealthy and exchange goods and ideas from one place to another. We also use water to clean ourselves off. If we don't we can become sick with illnesses that can harm our bodies.
Explanation:
Answer: R = 394.36ohm
Explanation: In a LR circuit, voltage for a resistor in function of time is given by:
![V(t) = \epsilon. e^{-t.\frac{L}{R} }](https://tex.z-dn.net/?f=V%28t%29%20%3D%20%5Cepsilon.%20e%5E%7B-t.%5Cfrac%7BL%7D%7BR%7D%20%7D)
ε is emf
L is indutance of inductor
R is resistance of resistor
After 4s, emf = 0.8*19, so:
![0.8*19 = 19. e^{-4.\frac{22}{R} }](https://tex.z-dn.net/?f=0.8%2A19%20%3D%2019.%20e%5E%7B-4.%5Cfrac%7B22%7D%7BR%7D%20%7D)
![0.8 = e^{-\frac{88}{R} }](https://tex.z-dn.net/?f=0.8%20%3D%20e%5E%7B-%5Cfrac%7B88%7D%7BR%7D%20%7D)
![ln(0.8) = ln(e^{-\frac{88}{R} })](https://tex.z-dn.net/?f=ln%280.8%29%20%3D%20ln%28e%5E%7B-%5Cfrac%7B88%7D%7BR%7D%20%7D%29)
![ln(0.8) = -\frac{88}{R}](https://tex.z-dn.net/?f=ln%280.8%29%20%3D%20-%5Cfrac%7B88%7D%7BR%7D)
![R = -\frac{88}{ln(0.8)}](https://tex.z-dn.net/?f=R%20%3D%20-%5Cfrac%7B88%7D%7Bln%280.8%29%7D)
R = 394.36
In this LR circuit, the resistance of the resistor is 394.36ohms.
Answer:
Explanation:
Momentum change for either skater is mΔv = 75.0(5.0) = 375 kg•m/s
As a change in momentum is equal to an impulse
375 = FΔt
F = 375/0.100 = 3750 N
As 3750 N < 4500 N no bones are broken.