.A 5.5kg riffle fires an 11gram bullet with a velocity of 1000m/s.
a. find the velocity of a riffle?
b. if the shooter holds the riffle firmly with his shoulder what will be the velocity assume the mass of shooter is 120kg?
2 answers
Use conservation of momentum to solve this.
Solution
*Let,
m1= 0.011 kg
v1= 1000 m/s
m2=5.5 kg and
v2= be the recoil velocity
*Equation:
M1V1+M2V2=0
a. (0.011 kg)(1000 m/s) + (5.5 kg)(v2)=0
11 kgm/s + 5.5 kgv2 = 0
5.5 kgv2 = -11 kg
v2= -2 m/s
b. (0.011 kg)(1000 m/s) + (120 kg + 5.5 kg)(v2)=0
11 kgm/s + 125.5 kgv2 = 0
125.5 kgv2 = -11 kgm/s
V2= -0.9 m/s or -9 cm/s
*Let,
m1= 0.011 kg
v1= 1000 m/s
m2=5.5 kg and
v2= be the recoil velocity
*Equation:
M1V1+M2V2=0
a. (0.011 kg)(1000 m/s) + (5.5 kg)(v2)=0
11 kgm/s + 5.5 kgv2 = 0
5.5 kgv2 = -11 kg
v2= -2 m/s
b. (0.011 kg)(1000 m/s) + (120 kg + 5.5 kg)(v2)=0
11 kgm/s + 125.5 kgv2 = 0
125.5 kgv2 = -11 kgm/s
V2= -0.9 m/s or -9 cm/s