In a \"ballistic pendulum,\" the bullet is fired at a massive pendulam bob that
ID: 2094969 • Letter: I
Question
In a "ballistic pendulum," the bullet is fired at a massive pendulam bob that is hanging straight downward at rest. The bullet emeds itself in the bob, and the bob+bullet together swing up to some maximum height before pausing to swing back downward.
A. If the bullet has a mass of 30 grams, the bob's mass is 3.5 kg, and the bob+bullet reach a height of 43 cm after impact, what is the speed of the bullet before impact?
B. If the length of the pendualum arm is 1.5 m, what maximum angle of displacment does the pendulum arm reach? (Please show work)
Explanation / Answer
Here
Loss in Kinetic Energy = Gin in Potential Energy
Therefore
0.5*30*10^-3*v^2 = (3.5+30*10^-3)*9.8*0.43
Therefore
we get
v = 31.49 m/sec
============================
Height Attained = L(1 - Cos(theta))
Here L = 1.5 m
Therefore
1.5*(1 - Cos(theta)) = 0.43
theta = 44.49 degree