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A toy cannon uses a spring to project a 5.26 g soft rubber ball. The spring is originally compressed by 4.93 cm and has a stiffness constant of 7.90 N/m. When it is fired, the ball moves 14.6 cm through the horizontal barrel of the cannon, and there is a constant frictional force of 0.0328 N between barrel and ball.

(a) With what speed does the projectile leave the barrel of the cannon?

m/s

(b) At what point does the ball have maximum speed?

cm (from its original position)

(c) What is this maximum speed?

m/s


answer and process please

User Borfast
by
4.5k points

1 Answer

10 votes

Answer:

a)
v=1.102122995 \approx 1.10m/s

b)
x=0.0451m

c)
v_m=1.75m/s

Step-by-step explanation:

From the question we are told that

Mass of soft rubber
M_r= 5.26g=>0.00526kg

Spring compression
d_C= 4.93 cm=>0.0493m

Stiffness constant
k= 7.90 N/m

Ball Distance
d=14.6=>0.146

Frictional force
f=0.0328 N

a)Generally the equation for motion of the second ball according to Newton's law is given by


(1)/(2)kc^2-f\triangle x=(1)/(2) mv^2


v=\sqrt{(k*d_c^2-2f\triangle x)/(m)}


v=\sqrt{((7.90 )(0.0493)^2-2*(0.0328)(0.0493+0.146))/(0.00526)}


v=1.102122995 \approx 1.10m/s

b)Generally for speed to be at maximum spring force must equal frictional force

At distance


f=kc'


d_c'=f/k


d_c'=0.0328 /7.90


d_c'=0.004151898734=>0.0042m

Therefore

Ball is at maximum speed at


x=d_c-d_c'


x=0.0493-0.0042


x=0.0451m

c)Generally maximum velocity is represented mathematically as


(1)/(2)kc^2-f\triangle x'=(1)/(2) mv'^2+(1)/(2)kc'^2


(1)/(2) mv'^2 = (1)/(2)kc^2-f\triangle x'-(1)/(2)kc'^2\\


v=\sqrt{(k*d_c^2-2*f*x-kd_c'^2)/(m)}


v=\sqrt{(7.90 *0.0493^2-2*(0.0328)*(0.0451)-7.90(0.0042)^2)/(0.00526)}


v=1.749685197m/s


v_m=1.75m/s

User Ronser
by
5.6k points