Answer:
Total energy = 1000J
KE = 500J
PE = 500J
Explanation:
As you may know, the equation for gravitational potential energy is mgh (weight x height)
If the skateboard is halfway down, that means it is at half the height. As the skateboard speeds up (as it goes downward), the potential energy becomes kinetic energy. Since it has 500J of kinetic energy at half way down, it means it had double that amount of Potential energy at the top (1000J). Since half of that became kinetic energy, there is only 500J of PE left.
Total energy = KE + PE = 1000J
KE = 500J
PE = 500J
Answer:
Elements in a period have wide range of chemical properties.
Explanation:
- Period is the row of chemical elements's arrangement in the periodic table. It is numbered from 1 to 7.
- In period as we move towards right the atomic number of element constantly increases along with the change in chemical properties.
- As we move from left towards right in period, the valence electron number regularly increases in every element.
- This valence electron differs the reactivity of the elements.
Answer:
n=6.56×10¹⁵Hz
Explanation:
Given Data
Mass=9.1×10⁻³¹ kg
Radius distance=5.3×10⁻¹¹m
Electric Force=8.2×10⁻⁸N
To find
Revolutions per second
Solution
Let F be the force of attraction
let n be the number of revolutions per sec made by the electron around the nucleus then the centripetal force is given by
F=mω²r......................where ω=2π n
F=m4π²n²r...............eq(i)
as the values given where
Mass=9.1×10⁻³¹ kg
Radius distance=5.3×10⁻¹¹m
Electric Force=8.2×10⁻⁸N
we have to find n from eq(i)
n²=F/(m4π²r)
