Answer:
D
Explanation:
this is simple, because when air is removed, means that there is no particles in the jar so vacuum is achieved, and when you can't hear a sound means that the sound couldn't travel through the vacuum. which means that sound cannot travel through vacuum,
as a result, sound requires a medium ( air) travel from one point to another.
hope it helps, if not please report it so that someone else gets to try it
Answer: 30 metres
Explanation:
Initial velocity of object = 120m/s
Time taken = 4.0s
Distance covered by object = ?
Recall that distance = (Change in velocity / Time taken)
Distance = (120m/s)/4.0s
= (120m/s) / 4.0s
= 30m
Thus, the object will be 30 metres high
Answer:
Because the energy is waning
Explanation: hope this helps
Answer:
The density of the metal is 5200 kg/m³.
Explanation:
Given that,
Weight in air= 0.10400 N
Weight in water = 0.08400 N
We need to calculate the density of metal
Let
be the density of metal and
be the density of water is 1000kg/m³.
V is volume of solid.
The weight of metal in air is



.....(I)
The weight of metal in water is
Using buoyancy force


We know that,
....(I)
Put the value of
in equation (I)

Put the value of Vg in equation (II)



Hence, The density of the metal is 5200 kg/m³.
Answer:
All the elements of a period have similar chemical properties because they have the same number of valence electrons in their outermost shell. Their atoms have the same number of electrons in the highest occupied energy level