Answer:
0 J
Explanation:
Kinetic energy is defined as:
KE = 1/2 m v²
where m is mass and v is velocity.
The car starts at rest, so it has zero velocity. Therefore, its initial kinetic energy is 0 J.
I'm not sure if this is correct but it's what I'll do
This is free-fall problem.
Stone A is thrown upward, at the point it falls down to the place where it was thrown, the velocity is -15m/s.
Now I choose the bridge is the origin. From the bridge, stone A and B fall the same distance which means Ya = Yb ( vertical distance )
Ya = Vo(t + 2) + 1/2a(t+2)^2
= -15(t + 2) + 1/2(9.8)(t^2 + 4t + 4)
= -15t - 30 + 4.5(t^2 + 4t + 4)
= -15t - 30 + 4.5t^2 + 18t + 18
= 4.5t^2 +3t - 12
Yb = Vo(t) + 1/2a(t)^2
= 0 + 4.5t^2
4.5t^2 = 4.5t^2 +3t - 12
0 = 3t - 12
4 = t
Time for Stone B is 4s
Time for Stone A is 6s
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.
A) The lifter's and the barbell's force are equal and opposite in direction
B) The lifter's force is greater than that of the barbell and in the upward direction
C) The barbell's force is greater than that of the lifter and in the downward direction
