Answer
Gravitational force is between two object caused by energy in mass. Here when you are in a mine the radius of the earth in case of calculating gravity is reduced to the length between you and the center.
This means the mass of earth is decreasing even though the distance is decreasing. Relative to the decrease in distance squared the decrease in the mass of the second object(earth) is more. As a result your weight decreases.
They are called mechanical waves
Answer: D. 1,2,3
The paper pots used
in steamboat restaurants will not catch fire when in contact with the flame for
the heat is conducted quickly to the water because the paper is thin and the burning
temperature of the paper is much higher than the boiling point of water. Lastly, the texture of the paper is thick that it can withstand the temperature of the flame.
Answer:
d. None of the above.
Explanation:
In a parabolic motion, you have that in the complete trajectory the component velocity is constant and the vertical component changes in time. Then, the total velocity vector is not zero.
In the complete trajectory the gravitational acceleration is always present. Then, the grasshopper's acceleration vector is not zero.
At the top of the arc the grasshopper is not at equilibrium because the gravitational force is constantly acting on the grasshopper.
Then, the correct answer is:
d. None of the above.
