Coal is the answer to the question
Answer:
An elastic collision is a collision in which there is no net loss in kinetic energy in the system as a result of the collision. Both momentum and kinetic energy are conserved quantities inelastic collisions.
Explanation:
Suppose two similar trolleys are traveling toward each other with equal speed. They collide, bouncing off each other with no loss in speed. This collision is perfectly elastic because no energy has been lost. In reality, examples of perfectly elastic collisions are not part of our everyday experience. Some collisions between atoms in gases are examples of perfectly elastic collisions. However, there are some examples of collisions in mechanics where the energy lost can be negligible. These collisions can be considered elastic, even though they are not perfectly elastic. Collisions of rigid billiard balls or the balls in Newton's cradle are two such examples.
Answer:
66.02m/s
Explanation:
the equation describing the distance covered in the horizontal direction is
but the acceleration in the horizontal path is zero, hence we have

Since the horizontal distance covered is 155m at 7.6secs, we have 
Also from the vertical path, the distance covered is expressed as

since the horizontal distance covered in 7.6secs is 195m, then we have

Hence if we divide both equation 1 and 2 we arrive at

Hence if we substitute the angle into the equation 1 we have

Hence the initial velocity is 66.02m/s
Answer:
Explanation:
Ionic bonding is stronger than any of the given intermolecular forces, but is itself NOT an intermolecular force. Ionic bonds are a permanent chemical connection between two atoms, whereas intermolecular forces as a more transient and temporary attraction between independent molecules
The metallic bond is somewhat weaker than the ionic and covalent bond. Ionic bonds are strong electrostatic attraction forces formed between positive and negative ions. This bond is non-directional, meaning that the pull of the electrons does not favor one atom over another.
Ion-dipole forces are the strongest of the intermolecular forces. ... However, hydrogen bonds are still not as strong as ion-dipole interactions. In order from strongest to weakest, the intermolecular forces given in the answer choices are: ion-dipole, hydrogen bonding, dipole-dipole, and Van der Waals forces.
Van der Waals forces are driven by induced electrical interactions between two or more atoms or molecules that are very close to each other. Van der Waals interaction is the weakest of all intermolecular attractions between molecules