They can't hear an echo in small room because in it the sound can't be reflected back. For an echo of a sound to be heard,the minimum distance between the source of sound and the walls of the roomshould be 17.2 m. Obviously,in asmall room echoes cannot beheard.
In the presence of air resistance, a watermelon is launched into the air with 100 j of kinetic energy.
Its kinetic energy is less than 100 J when it reaches its starting point. Its kinetic energy decreases as it encounters air resistance and returns to its starting point. In actuality, some of the energy has been lost because of air resistance. Since we use the ball's original height as a point of reference, there is no potential energy when the ball is in its initial state of motion, and K is its kinetic energy. This total energy is conserved if there is no air resistance, therefore when the ball returns to its starting position, its kinetic energy will remain at 100.
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The transfer of internal energy in the form of electromagnetic waves.
Answer:
value-added tax (VAT) is a consumption tax that is levied on a product repeatedly at every point of sale at which value has been added. ... VAT is commonly expressed as a percentage of the total cost. For example, if a product costs $100 and there is a 15% VAT, the consumer pays $115 to the merchant.
Explanation:
archemdes principle states that the boyant upward force by liquid is equal to liquid displaced by solid...
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Positive - Friction allows us to create heat in a desperate situation, like being lost in the woods. If we didn't have friction, we would probably freeze to death.
Negative - Friction can also cause unwanted fires, such as forest fires. If friction didn't exist, we wouldn't have these.