Explanation:
The strength of the gravitational force between two objects depends on two factors, mass and distance. the force of gravity the masses exert on each other. ... increases, the force of gravity decreases. If the distance is doubled, the force of gravity is one-fourth as strong as before.
It would be the first option.
Explanation-
The number of protons is equal to the atomic number the number of neutrons is the mass minus the atomic number.
What is the Investigation about!
Answer:
The amount of work done required to stretch spring by additional 4 cm is 64 J.
Explanation:
The energy used for stretching spring is given by the relation :
.......(1)
Here k is spring constant and x is the displacement of spring from its equilibrium position.
For stretch spring by 2.0 cm or 0.02 m, we need 8.0 J of energy. Hence, substitute the suitable values in equation (1).

k = 4 x 10⁴ N/m
Energy needed to stretch a spring by 6.0 cm can be determine by the equation (1).
Substitute 0.06 m for x and 4 x 10⁴ N/m for k in equation (1).

E = 72 J
But we already have 8.0 J. So, the extra energy needed to stretch spring by additional 4 cm is :
E = ( 72 - 8 ) J = 64 J
Answer:
Explanation:
When the two or more forces acting on a body such tat the net force on the body or the acceleration of the body is zero, then such forces are balanced forces.
For example, in the game of tug of war, both the teams pulls the rope with same force but in opposite directions so that the net acceleration is zero it means a balanced force is acting on the rope.
When tow or more forces acting on a body and there is some net force or acceleration of the body, then the forces are said to be unbalanced.
For example, if we push a box along the plane, the net force is non zero and the forces are unbalanced.