Answer:
u = 7.74 m/s and t = 1.82 s
Explanation:
Given that,
Harold threw a baseball 3 meters.
Harold is 2 meters tall.
The vertical distance = 3m
The final velocity at the maximum height is 0.
Let u is the initial velocity of the baseball. Using the first equation of motion to find it as follows :
Here, a = -g
He has thrown it with the speed of 7.74 m/s
Let t is the time taken by the ball to fall on the ground.
Harold is 2 meters tall. Using second equation of motion to find it.
u = -7.74 (as downward direction is taken as positive)
Hence, this is the required solution.
Answer:
A closed system.
Explanation:
The three major types of system are: open, closed and isolated. Open system interacts with its surroundings with respect to its particles and energy. A closed system interacts with its surroundings with respect to energy but not its particles. While an isolated system does not interact with its surroundings in any way.
Therefore, after the jar is sealed, it is an example of a closed system. This is because the emitted gas could not escape into the surroundings, but thermal energy was emitted into its surroundings after the chemical reaction has taken place.
It is malleable
Explanation:
The property that makes metals such as sterling silver the best to create hammered earrings is their malleability.
All metals have a unique and fascinating property of being malleable. They can be carved into any of shape. When hammered they simply draw out and retain their long range ordering of their crystal lattice.
This is made possible by the presence of metallic bonding between the atoms.
- The bulk of the physical properties of metals can be attributed the metallic bonds in them.
- Metals have large sea of electrons in them.
- In forming metallic bonds, there is an attraction between the positive nuclei of all the closely packed atoms in the lattice and the electron cloud jointly formed by all the atoms by loosing their outermost shell electrons.
- Metals like silver have low ionization energy.
- When they are hammered, they spread out the energy from the hammering.
learn more:
Metals brainly.com/question/2474874
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