Ball A leaves the edge of a level table with speed v and falls to the floor. At

Question

Ball A leaves the edge of a level table with speed v and falls to the floor. At the instant ball A leaves the table edge, s 0 +- another identical ball, B, is released from rest at the height of the table top and also falls to the floor. It is observed that the balls reach the floor at the same time. In each question below, consider the interval that begins when the balls begin falling and ends just before they reach the floor. a. Is the magnitude of the impulse imparted to ball B greater than, less than, or equal to the magnitude of the impulse imparted to ball A? Explain your reasoning. i. ii. In the spaces provided at right, draw an arrow to Direction of the impulse imparted to - indicate the direction of the impulse imparted to each ball. Explain your reasoning. Ball A Ball B ii. Is the work done on ball B greater than, less than, or equal to the work done on ball A? Explain your reasoning. In each question below, consider the balls just before they reach the floor. i. Is the magnitude of the momentum of ball B greater than, less than, or equal to the b. magnitude of the momentum of ball A? Explain your reasoning. i. Is the kinetic energy of ball B greater than, less than, or equal to the kinetic energy of ball A? Explain your reasoning.

Explanation / Answer

(1) (a)

(i) impulse = force x time = mass x change in velocity

for both balls, the vertical component of velocity during the considered time interval does not change. this means that no impulse is provided. Hence magnitude of impulse imparted to ball B is equal to that of ball A.

(ii) impulse imparted to ball A is in horizontal direction only and is given by below arrow

<----------

There is no impulse provided to ball B.

(iii) W = F.d, since both balls fell through the same distance, the work done on both the balls is equal.

(b)

(i) Considering relation v2 - u2 = 2gh

for ball A, u = vAi and for ball B, u = 0

hence the magnitude of v will be greater for ball A. since balls are identical in mass and momentum = mass * velocity, ball A will have higher momentum than B.

(ii) since v is higher for ball A than B, and Kinetic energy = (1/2) mv2

ball A will have greater kinetic energy than ball B.

Related Questions

Navigate

• Browse (All)
• Browse B
• Subjects

---

---

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