A jogger runs on the track shown in Figure 2-24, where L = 140 m and W = 30 m. Neglect the curvature of the corners in your answers to the following questions.

Figure 2-24

(a) What is the distance traveled and the displacement in running from point A to point B?

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1 m (distance)

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2 m (displacement)
(b) Find the distance and displacement for a complete circuit of the track.

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3 m (distance)

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4 m (displacement)

A crow is flying horizontally with a constant speed of 3.25 m/s when it releases a clam from its beak (Figure 4-16). The clam lands on the rocky beach 1.70 s later. Consider the moment just before the clam lands. (Neglect air resistance.)

Figure 4-16

(a) What is its horizontal component of velocity?

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1 m/s
(b) What is its vertical component of velocity?

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2 m/s
(c) Select all of the following which would apply to your answers for (a) and (b), if the speed of the crow were decreased.

3

The vertical component would increase. The horizontal component would decrease. The vertical component would decrease. The horizontal component would increase.

Explain.
4

The two masses in the Atwood's machine shown in Figure 8-20 are initially at rest at the same height. After they are released, the large mass, m₂, falls through a height h and hits the floor, and the small mass, m₁, rises through a height h.

Figure 8-20

(a) Find the speed of the masses just before m₂ lands. Assume the ropes and pulley have negligible mass and that friction can be ignored. (Use m_1 for m₁, m_2 for m₂, and h and g as necessary.)

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1

(b) Evaluate your answer to part (a) for the case where h = 1.0 m, m₁ = 3.5 kg, and m₂ = 4.1 kg.

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2 m/s

Four masses are positioned at the corners of a rectangle, as indicated in Figure 12-23 (not to scale).

Figure 12-23

(a) Find the magnitude and direction of the net force acting on the 2.0 kg mass if x = 0.38 m and y = 0.14 m.

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1 N (magnitude)

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2° counterclockwise from the x-axis, which points to the right

(b) How do your answers to part (a) change (if at all) if all sides of the rectangle are doubled in length?

3

The magnitude of the force will be unchanged. The magnitude of the force will be reduced by a factor of two. The magnitude of the force will be reduced by a factor of four. The direction will remain unchanged. The direction will shift clockwise. The direction will shift counterclockwise.

Complete the fission reaction below. (Type your answer using the format 14C for ¹⁴₆C, and any symbols from the following table.)

¹₀n + ²³⁵₉₂U ⁹⁴₃₈Sr +

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1 + 6 ¹₀n

Determine the amount of energy released.

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2 MeV