An object of mass 3m moves in the +x direction at 3 m/s. it breaks into two pices of mass m and 2m. mass 2m moves in a direction 30 degrees above the x-axis and mass m moves in a direction 45 degrees below the x-axis. there is no gravity or air resistance to consider. find the final velocities of the two masses.

Explanation:

Given

Initial mass 3 M

initial velocity u=3 m/s

3 M breaks into 2 M and M with velocity and

conserving momentum in x direction

-------------1

conserving Momentum in Y direction

substitute in 1

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.