Answer: Bohr's model (1913)
Niels Bohr improved Rutherford's model. Using mathematical ideas, he showed that electrons occupy shells or energy levels around the nucleus. The Dalton model has changed over time because of the discovery of subatomic particles.
Bohr's model (1913)
Niels Bohr improved Rutherford's model. Using mathematical ideas, he showed that electrons occupy shells or energy levels around the nucleus. The Dalton model has changed over time because of the discovery of subatomic particles
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.
John Dalton
The idea that everything is made of atoms was pioneered by John Dalton (1766-1844) in a book he published in 1808. He is sometimes called the "father" of atomic theory, but judging from this photo on the right "grandfather" might be a better term.
Explanation:
Answer:
The answer is A, B, C and D
Explanation:
(is that how it works?)
Given parameters;
Time taken to complete a lap = 8.667s
Radius of flower = 13.9cm
convert to SI unit of m, 100cm = 1m
13.9cm gives 
= 0.139m
Unknown = speed
To solve this problem, we need to first find the circumference of the flower.
Circumference of the circular flower = 2 π r
where r is the radius of the flower;
Circumference = 2 x 3.142 x 0.139 = 0.87m
Now to find the how fast the bug is travelling,
Speed = 
Since the bug covered 1 lap, the distance is 0.87m
Now input the parameters and solve for speed;
Speed = 
= 0.1m/s
The bug is travelling at a speed of 0.1m/s
Wave speed = (frequency) x (wavelength)
= (5 / second) x (30 mm)
= 150 mm/second = 0.15 meter/second .
