Suppose that a constant force is applied to an object. newton's second law of motion states that the acceleration of the object varies inversely with its mass. a constant force acting upon an object with mass 8kg produces an acceleration of 7m/s (squared) . the acceleration of another object produced by the same force is 4m/s(squared) . what is the mass of this object?

An ideal spring has a spring constant (force constant) of 2500 n/m, is stretched 4.0 cm, how much elastic potential energy does it possess? (a) 3j (b) 0.00j (c) 1j (d) 2j (e) 4j

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 710 n/m. it is initially at rest on an inclined plane that is at an angle of θ = 23° with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is μk = 0.19. in the initial position, where the spring is compressed by a distance of d = 0.16 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. a) what is the block's initial mechanical energy? b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?