Asquare block with mass m = 100g and side length s = 3.0cm resting on a flat surface at height h = 15cm at an angle θ = 30omeasured from the x-axis is struck by a spring driven plunger with spring constant k1 = 10. the coefficients of friction between the block and all surfaces are µs = .2 & µk = .1 the initial velocity of the block after being struck is v0 = 1.25 m s 2.2 problems 2.2.1 where does the block come to rest? assume: a) the second spring is level with the ground and exerts exactly enough force to change the y-component of the block’s velocity b) the block lands on the very edge of the second raised area at the top of its motion after reboundin

measure their densities same density, same sub

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.

conservation of mass

mass before something happens = mass afterwards