The mass is just sitting there motionless. There is no acceleration and it is in equilibrium. What does this mean? This means that the net force in the y-direction (vertical direction) must be zero. I ...

To investigate experimentally the extension of a spring and how it is related to the applied force, and recall that the extension of a spring is directly proportional to the force applied, provided ...

Forces may change the shape of an object. An elastic object, such as a spring, stores elastic potential energy when stretched or squashed. The extension of an elastic object is directly proportional ...