Answer:
The number of protons in an atom is different than the atom's total mass.
Explanation:
Mendeleev had presented the first structured periodic table in 1869. But, in 1913, Henry Moseley developed the modern periodic table. The crucial difference between the two periodic tables is that Mendeleev's periodic table is generated on the basis of the atomic masses of chemical elements while the chemical element's atomic numbers were the main focus of Moseley's periodic table. There were just 56 chemical elements in Mendeleev's periodic table. On the other hand, 74 chemical elements are presented in Moseley's periodic table.
<h2>
a)Time taken is 12.90 seconds</h2><h2>
b) Time taken is 72.46 seconds</h2>
Explanation:
Let east be positive x axis and north be positive y axis
Speed = 1.60 m/s in a direction that is 15.0° north of east.
Speed, v = 1.60 cos 15 i + 1.60 sin 15 j = 1.55 i + 0.414 j m/s
a) We need to find time taken to travel 20 m along east
Speed along east = 1.55 m/s
Distance = Speed x Time
20 = 1.55 x Time
Time = 12.90 seconds
Time taken is 12.90 seconds
b) We need to find time taken to travel 30 m along north
Speed along north = 0.414 m/s
Distance = Speed x Time
30 = 0.414 x Time
Time = 72.46 seconds
Time taken is 72.46 seconds
Answer:
The mass of the skateboard is 1.25 kg.
Explanation:
We have,
Mass of dog, m = 5 kg
Initial speed of dog, u = 2.5 m/s
Initial speed of skateboard, u' = 0 (at rest)
The dog jumps onto the skateboard and both the dog and skateboard move with a speed of 2.00 m/s. It is the common speed of the dog +skateboard, V = 2 m/s. We need to find the mass of the skateboard. Using conservation of momentum as :
m' is mass of skateboard
So, the mass of the skateboard is 1.25 kg.
The bike rider hitting his bike or the car.
