a) What is the magnitude of the cannon\'s velocity, v c after the rough potato l

Question

a) What is the magnitude of the cannon's velocity, vc after the rough potato leaves the muzzle?

b) What is the total mechanical energy (potential and kinetic) of the potato/cannon system before the firing of the potato?

c) What is the total mechanical energy (potential and kinetic) of the potato/cannon system after the firing of the potato?

d) What is the work, Wf, done by the force of friction on the rough potato?

A potato cannon is used to launch a potato on a frozen lake, as shown in the figure. The mass of the cannon, mc is 14.7 kg, and the mass of the potato, mpr is 0.753 kg. The cannon's spring (with spring constant 7.15-103 N/m) is compressed x 2.00 m. Prior to launching the potato, the cannon is at rest. The potato has a large diameter and is very rough, causing friction between the cannon be and the potato. The rough potato leaves the cannon's muzzle moving horizontally to the right at a speed of vp 153 m/s. Neglect the effects of the potato spinning. Assume there is no friction between the cannon and the lake's ice

Explanation / Answer

A) by momentum conservation,

mcVc = mpVp

Vc = (0.753*153)/14.7

= 7.84 m/s

B) initial energy = spring energy = 0.5 kx^2

= 0.5*7150*2^2

= 14300 J

C) Total mechanical energy = sum of both KE

= 0.5*0.753*153^2 + 0.5*14.7*7.84^2

= 9265 J

D) work done by friction on both = 9265-14300

= - 5035

Work done by friction on potato Wp

= - 5035*(153/(153+7.84))

= - 4790 J answer

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.