Answer:
5.7141 m
Explanation:
Here the potential and kinetic energy will balance each other
![mgh=\frac{1}{2}mv^2\\\Rightarrow v=\sqrt{2gh}](https://tex.z-dn.net/?f=mgh%3D%5Cfrac%7B1%7D%7B2%7Dmv%5E2%5C%5C%5CRightarrow%20v%3D%5Csqrt%7B2gh%7D)
This is the initial velocity of the system and the final velocity is 0
t = Time taken = 0.04 seconds
F = Force = 18000 N
a = Acceleration
g = Acceleration due to gravity = 9.81 m/s²
Equation of motion
![v=u+at\\\Rightarrow a=\frac{v-u}{t}](https://tex.z-dn.net/?f=v%3Du%2Bat%5C%5C%5CRightarrow%20a%3D%5Cfrac%7Bv-u%7D%7Bt%7D)
From Newton's second law
![F=ma\\\Rightarrow F=m\frac{v-u}{t}\\\Rightarrow 18000=68\frac{0-\sqrt{2gh}}{0.04}\\\Rightarrow \frac{18000}{68}\times 0.04=-\sqrt{2\times 9.81\times h}\\\Rightarrow 10.58823=-\sqrt{2\times 9.81\times h}](https://tex.z-dn.net/?f=F%3Dma%5C%5C%5CRightarrow%20F%3Dm%5Cfrac%7Bv-u%7D%7Bt%7D%5C%5C%5CRightarrow%2018000%3D68%5Cfrac%7B0-%5Csqrt%7B2gh%7D%7D%7B0.04%7D%5C%5C%5CRightarrow%20%5Cfrac%7B18000%7D%7B68%7D%5Ctimes%200.04%3D-%5Csqrt%7B2%5Ctimes%209.81%5Ctimes%20h%7D%5C%5C%5CRightarrow%2010.58823%3D-%5Csqrt%7B2%5Ctimes%209.81%5Ctimes%20h%7D)
Squarring both sides
![112.11061=2\times 9.81\times h\\\Rightarrow h=\frac{112.11061}{2\times 9.81}\\\Rightarrow h=5.7141\ m](https://tex.z-dn.net/?f=112.11061%3D2%5Ctimes%209.81%5Ctimes%20h%5C%5C%5CRightarrow%20h%3D%5Cfrac%7B112.11061%7D%7B2%5Ctimes%209.81%7D%5C%5C%5CRightarrow%20h%3D5.7141%5C%20m)
The height from which the student fell is 5.7141 m
“Magnets are surrounded by an invisible magnetic field that is made by the movement of electrons, the subatomic particles that circle the nucleus of an atom”
“Every magnet has both a north and a south pole. When you place the north pole of one magnet near the south pole of another magnet, they are attracted to one another. When you place like poles of two magnets near each other (north to north or south to south), they will repel each other.”
Answer:
There are Microwaves, the type of electro magnetic radiation is a Micro-wave. We use x-rays, the type of electro magnetic radiation is a gamma wave. We also use radios, the type of electro magnetic radiation is a radio wave.
Explanation:
I remember doing this assignment too
Answer:
A. I and V
Explanation:
According to Le Chatelier's Principle, increasing the product side will cause the equilibrium to shift back towards the reactant side, so I is true. By the same principle, II is false.
For gases, decreasing the pressure will cause the equilibrium to shift towards the side with higher number of moles. So V is true.
The reaction is endothermic, so increasing the temperature will shift the equilibrium to the products, so IV is false. And adding a catalyst has no effect on the equilibrium, so III is false.
Reactants
In a chemical reaction, the substances that undergo change are called reactants. The new substances formed as a result of that change are called products.