a werewoflf vaulting over a fence is spotted by some hunters. The hunters shoot
ID: 2260550 • Letter: A
Question
a werewoflf vaulting over a fence is spotted by some hunters. The hunters shoot a specially molded silver bullet and hit the creature in the shouldr. With a diplay of incredible stenght the werewolf hold on to the bar and beings to rotate similar to a gymnast. Asume grictinless rotation. Mass of the Bullet=0.05kg, Initial Velocity of Bulllet =100m/s, Moment of interi fof werwolf =23.33 kg*m^2, r= 1.0m (distance from axis of raotation to bullet strike.
a) find the angular velocity of the werewolf after the collison
b_ is kinetic energy conserved when comparing teh system before and after the collision?
c)if the bullet comes to rest in the werewolf in 0.05 seonds what torque does the werewolf experience?
Please help
Explanation / Answer
a) conserving Angular momentum for bullet wolf system
Angular momentum of bullet about axis of rotation = (MOI of Wolf + MOI of bullet) * new angular velocity
Angular momentum of bullet about axis of rotation = mvr = 0.05*100*1 = 5 kg m^2/s
MOI of bullet = m*r*r = 0.05 kg m^2
New angular velocity = angular velocity of warewolf = 5 / (23.33+0.05) = 0.2138 rad/s
b) No, kinectic energy is decreased.
Initial = m*v*v/2 = 250 J
Final = (I1+I2)*w*w/2 = (23.33+0.05)*.2138*.2138/2 = 0.534 J
c) torque = change in angular momentum / time
= I * omega / time = 23.33 * .2138 / 0.05 = 99.76 Nm
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.