Answer:
A device that does work with only one movement and changes the size or direction of a force is a simple machine.
Explanation:
- For applying force, any used basic mechanical devices are simple machines.
- Simple machine changes the direction as well as the amplitude of the applied force i.e. we can increase or decrease the magnitude of the force.
- A simple machine is the most basic mechanism to use the force as we need in big mechanical machines.
- Some of the examples of simple machines are inclined plane, lever, wedge, wheel and axle, pulley, and screw.
Gets exited and moves at a faster constant speed
There will be 7.5 g of Be-11 remaining after 28 s.
If 14 s = 1 half-life, 28 s = 2 half-lives.
After the first half-life, ½ of the Be-11 (15 g) will disappear, and 15 g will remain.
After the second half-life, ½ of the 15 g (7.5 g) will disappear, and 7.5 g will remain.
In symbols,
<em>N</em> = <em>N</em>₀(½)^<em>n</em>
where
<em>n</em> = the number of half-lives
<em>N</em>₀ = the original amount
<em>N</em> = the amount remaining after <em>n</em> half-lives
Answer:
Th is the symbol for element Thorium.
Mg is magnesium while Mg 2+ is magnesium Ion. Judging from periodic trends, atomic radius is one half the distance between the atoms of two covalently bonded atoms. It decreases as elevtrons are added to valence shells. That means, across the period it increases and down the group it decreases. Making Mg2+ smaller.
Electronegativity is the energy needed to take an electron in the gaseous state. Florine is more electron negative that lithium. It increases across the period and decreases down the group. Except in the Noble group.
Explanation: