Mass always stays the same therefore it can’t be c and d. Volume stays the same because she is not removing anything. Therefore it is a
Answer:
Thats her fault.........................b
Explanation:
Mechanical advantage of a machine is the ratio of the output force over the input force or M=Fo/Fi. Since M=1, Fi=Fo, or the input force is equal to the output force. This means that to raise the refrigerator that weighs 900 N, we need the same input force of 900 N, or Fo=Fi=900 N.
Answer:
The sphere C carries no net charge.
Explanation:
- When brougth close to the charged sphere A, as charges can move freely in a conductor, a charge equal and opposite to the one on the sphere A, appears on the sphere B surface facing to the sphere A.
- As sphere B must remain neutral (due to the principle of conservation of charge) an equal charge, but of opposite sign, goes to the surface also, on the opposite part of the sphere.
- If sphere A is removed, a charge movement happens in the sphere B, in such a way, that no net charge remains on the surface.
- If in such state, if the sphere B (assumed again uncharged completely, without any local charges on the surface), is touched by an initially uncharged sphere C, due to the conservation of charge principle, no net charge can be built on sphere C.
Answer:
2.124 kg of water
Explanation:
height of the falls is about 48 meters.
Mass of water needed is 1kg = 1000g
Power needed is 106 watts.
The amount of energy in 106 watts in one sec is 106 joules.
To calculate the energy of the 1kg falling water = Mgh
Energy = 1000*9.81*48
Energy = 470880 joules.
1 megawatt is = 1000000watts
The kilogram of water needed is 1000000/470880 = 2.124 kg of water