Physics help, please! 10 points best.?

Question

A 15.5 gram piece of putty traveling fast at 425 m/s hits a 15 kg mass suspended in air by a thin thread. The piece of putty sticks to the mass and causes thread to break launching the mass and putty combination into projectile motion. The mass and putty falls a distance of 3.35 m to the ground.

A.) The system flies off horizontally a distance of 3.35 m to the ground in the vertical direction. How far in the x-direction did it fall?

B) Use the conservation of mechanical energy to calculate the speed of the system as it hits the ground.

electron1 · Accepted Answer

Let’s use conservation of momentum to determine the velocity after the collision.
Initial momentum = 0.0155 * 425 = 6.5875
Total mass = 0.0155 + 15 = 15.0155 kg
Final momentum = 15.0155 * v
15.0155 * v = 6.5875
v = 6.5875 ÷ 15.0155
This is approximately 0.439 m/s. Let’s determine the kinetic energy. Let’s use the following equation to determine the time for them to fall 3.35 meters.

d = vi * t + ½ * a * t^2, vi = 0, a = 9.8
3.35 = ½ * 9.8 * t^2
t = √(3.35/4.9)
This is approximately 0.827 seconds.

A.) The system flies off horizontally a distance of 3.35 m to the ground in the vertical direction. How far in the x-direction did it fall?

d = (6.5875 ÷ 15.0155) * √(3.35/4.9)
This is approximately 0.363 meter

Final vertical velocity = 9.8 * √(3.35/4.9)
This is approximately 8.1 m/s.
Final speed = √[(6.5875 ÷ 15.0155)^2 + 65.66]
This is approximately 8.114 m/s

KE = ½ * 15.0155 * (6.5875 ÷ 15.0155)^2 =  6.5875^2 ÷ 30.031
This is approximately 1.4445 joules. Let’s determine the potential energy.

PE = 15.0155 * 9.8 * 3.35 = 492.94245 J
Total = 492.94245 + 6.5875^2 ÷ 30.031 = 494.2741609 J
½ * 15.0155 * v^2 = 494.2741609 
v^2 = 494.2741609 ÷ 7.5075
v= √(494.2741609 ÷ 7.5075)
This is approximately 8.114 m/s. 
This is same answer.

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Physics help, please! 10 points best.?

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