> Non-zero numbers (like 1,2,3,4...) are always significant
> A zero sandwiched between two non-zero numbers is always significant
> Trailing zeros in a decimal (not whole number like million) are always significant.
<span>0,020170 = 2.0170 × 10^-2
5 sig-figs
</span>
Answer:
The kinetic energy is 86.6 zepto joules.
Explanation:
Given that,
Number of orbit n =5
We know that,
Bohr's radius for hydrogen atom is

Now, put the value of n in the formula of radius


We need to calculate the kinetic energy
Using formula of kinetic energy

Put the value into the formula


We know that,

The kinetic energy is


Hence, The kinetic energy is 86.6 zepto joules.
Answer:
Explanation:
All the rest of the information is extraneous. The only 2 things you have to know are
d = 20 km
t = 8 minutes = 8/60 hours = 0.13333333
So the speed is s = d/t
s = 20/0.1333333 = 150 km/hour
Note: you have not specified what units the speed is. I suppose you could answer 20/8 = 2.5 km/min
One scientist proposes an idea and other scientists repeat his or her experiments so they can Accept the Idea.