<span>Since there is no friction, conservation of energy gives change in energy is zero
Change in energy = 0
Change in KE + Change in PE = 0
1/2 x m x (vf^2 - vi^2) + m x g x (hf-hi) = 0
1/2 x (vf^2 - vi^2) + g x (hf-hi) = 0
(vf^2 - vi^2) = 2 x g x (hi - hf)
Since it starts from rest vi = 0
Vf = squareroot of (2 x g x (hi - hf))
For h1, no hf
Vf = squareroot of (2 x g x (hi - hf))
Vf = squareroot of (2 x 9.81 x 30)
Vf = squareroot of 588.6
Vf = 24.26
For h2
Vf = squareroot of (2 x 9.81 x (30 – 12))
Vf = squareroot of (9.81 x 36)
Vf = squareroot of 353.16
Vf = 18.79
For h3
Vf = squareroot of (2 x 9.81 x (30 – 20))
Vf = squareroot of (20 x 9.81)
Vf = 18.79</span>
Answer:
attracted
Explanation:
opposite charges attract each other when the rub against each other
Answer:
The difference in these is that the ovary of a fruit can be edible which forms to enclose around seeds while a tree grows up to have a different structure and means of reproduction/
Explanation:
Kinetic energy, KE, is modeled by the formula
![KE = \frac{1}{2}mv^2](https://tex.z-dn.net/?f=KE%20%3D%20%20%5Cfrac%7B1%7D%7B2%7Dmv%5E2)
, where m is the mass in kg and v is the velocity in m/s.
In this scenario, mass and one-half are constant but the velocity changes.
You can see that by squaring twice the velocity, that is equal to four times the original KE. Therefore, the answer is 4k.
Answer:
0.51 m
Explanation:
Using the principle of conservation of energy, change in potential energy equals to the change in kinetic energy of the spring.
Kinetic energy, KE=½kx²
Where k is spring constant and x is the compression of spring
Potential energy, PE=mgh
Where g is acceleration due to gravity, h is height and m is mass
Equating KE=PE
mgh=½kx²
Making x the subject of formula
![x=\sqrt {\frac {2mgh}{k}}](https://tex.z-dn.net/?f=x%3D%5Csqrt%20%7B%5Cfrac%20%7B2mgh%7D%7Bk%7D%7D)
Substituting 9.81 m/s² for g, 1300 kg for m, 10m for h and 1000000 for k then
![x=\sqrt \frac {2*1300*9.81*10}{1000000}=0.50503465227646m\\x\approx 0.51 m](https://tex.z-dn.net/?f=x%3D%5Csqrt%20%5Cfrac%20%7B2%2A1300%2A9.81%2A10%7D%7B1000000%7D%3D0.50503465227646m%5C%5Cx%5Capprox%200.51%20m)