B they formed from the dense elements as compared to the others in the solar system
No the substance will remain the same substance as before.
Answer:
Explanation:
Given
mass of boy ![m_b=70.9\ kg](https://tex.z-dn.net/?f=m_b%3D70.9%5C%20kg)
mass of girl ![m_g=43.2\ kg](https://tex.z-dn.net/?f=m_g%3D43.2%5C%20kg)
speed of girl after push ![v_g=4.64\ m/s](https://tex.z-dn.net/?f=v_g%3D4.64%5C%20m%2Fs)
Suppose speed of boy after push is ![v_b](https://tex.z-dn.net/?f=v_b)
initially momentum of system is zero so final momentum is also zero because momentum is conserved
![P_i=P=f](https://tex.z-dn.net/?f=P_i%3DP%3Df)
![0=m_b\cdot v_b+m_g\cdot v_g](https://tex.z-dn.net/?f=0%3Dm_b%5Ccdot%20v_b%2Bm_g%5Ccdot%20v_g)
![v_b=-\frac{m_g}{m_b}\times v_g](https://tex.z-dn.net/?f=v_b%3D-%5Cfrac%7Bm_g%7D%7Bm_b%7D%5Ctimes%20v_g)
![v_b=-2.82\ m/s](https://tex.z-dn.net/?f=v_b%3D-2.82%5C%20m%2Fs)
i.e. velocity of boy is 2.82 m/s towards west
You know that when the displacement is equal to the amplitude (A), the velocity is zero, which implies that the kinetic energy (KE) is zeero, so the total mechanical energy (ME) is the potential energy (PE).
And you know that the potential energy, PE, is [ 1/2 ] k (x^2)
Then, use x = A, to calculate the PE in the point where ME = PE.
ME = PE = [1/2] k (A)^2.
At half of the amplitude, x = A/2 => PE = [ 1/2] k (A/2)^2
=> PE = [1/4] { [1/2]k(A)^2 } = .[1/4] ME
So, if PE is 1/4 of ME, KE is 3/4 of ME.
And the answer is 3/4
Answer:
A collision in which both total momentum and total kinetic energy are conserved
Explanation:
In classical physics, we have two types of collisions:
- Elastic collision: elastic collision is a collision in which both the total momentum of the objects involved and the total kinetic energy of the objects involved are conserved
- Inelastic collision: in an inelastic collision, the total momentum of the objects involved is conserved, while the total kinetic energy is not. In this type of collisions, part of the total kinetic energy is converted into heat or other forms of energy due to the presence of frictional forces. When the objects stick together after the collision, the collisions is called 'perfectly inelastic collision'