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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.
Answer:
d. circuit
Explanation:
the parts of the circuit consists of a load or resistance
They tend to be lustrous, ductile, malleable, and good conductors of electricity, while nonmetals are generally brittle (for solid nonmetals), lack lustre, and are insulators. Use google.
Answer:
We apply force to move the brick.
Explanation:
Let me first of define a force .
A force is something applied to an object or thing to change it's internal or external state.
Now if a brick is resting on smooth wood inclined at 30° to the horizontal for us to overcome the friction which is also a force we have to apply a force greater than the gravity force acting on the body and then depending on the direction of the applied force the angle to apply it also.
