Answer:
It's an example of velocity.
Ke= 1/2 x m x v^2
Ke= 1/2 x 2.1 x 30^2
Energy = 945 J
Answer:
The correct answer is option b. At higher elevations, it would take longer to hard boil an egg, because there is a lower boiling.
Explanation:
When we boil water at a very high temperature, it turns out that the water boils much faster. This is because the higher we are, <u>there will be less oxygen and less pressure in the atmosphere</u>. This implies that the water vapor becomes steam much faster than as it happens at low temperatures, so less heat will be needed for the water to boil.
That is why <u>if we want to cook an egg, we will have to lower the heat</u> of the kitchen when we put it on the fire, in order to avoid boiling water very quickly. Lowering the heat, <u>then cooking the egg will take much longer.
</u>
Given this data, the correct answer is option B, At higher elevations, it would take longer to hard boil an egg, because there is a lower boiling.
Explanation:
Given that,
The mass of rock, m = 2.35-kg
It was released from rest at a height of 21.4 m.
(a) The kinetic energy is given by : 
As the rock was at rest initially, it means, its kinetic energy is equal to 0.
(b) The gravitational potential energy is given by : 
It can be calculated as :

(c) The mechanical energy is equal to the sum of kinetic and potential energy such that,
M = 0 J + 492.84 J
M = 492.84 J
Hence, this is the required solution.