I - ok. Czechoslovakia is officially taken.
Answer:
100Kg.m/s
Explanation:
From the question, we obtained the following information:
M= Mass = 25kg
V = Velocity = 4m/s
Momentum =?
Momentum = MV = 25x4= 100Kg.m/s
Answer:
See the explanation below
Explanation:
Density is defined as the relationship between mass and volume, i.e. the following equation can be used:
density = m/v
where:
density [kg/m^3]
m = mass [kg]
v = volume [m^3]
If we change the volume of a body by reducing its size, its mass will also decrease proportionally with a density as seen in the equation.
m = density*v
To understand this concept more clearly, let's use the following example:
We know that the density of water is equal to 1000 [kg/m^3], that is, 1 cubic meter of water contains 1000 kilograms of water, using the equation.
1000 = m /1
m = 1000*1 = 1000 [kg]
Now if we have 500 kilograms of water, that would pass with the volume so that the density remains constant.
1000 = 500/v
v = 500/1000
v = 0.5 [m^3]
We can see that the volume of water has halved. Since the mass of water was reduced by half. That is, the relationship between mass and volume is proportional to the density of the material or substance.
working...
Sound wave needs medium to travel
as energy which travels in this wave is because of transfer from one particle to another particle
If there is no medium then energy can not be transferred and sound wave will not travel
so in vacuum we can not listen sound
similarly here air is removed it means there is no medium inside the jar to travel the sound and hence we can not hear it
Option B is correct
Without air, the sound waves cannot travel to the ear.