Suppose that in the figure, the masses of the blocks are 2.0 kg and 4.0 kg.**(a) **Which mass should the hanging block have if the magnitude of the acceleration is to be as large as possible?**(b)** What then are the magnitude of the acceleration and**(c)** the tension in the cord?

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A block of mass *m*_{1} = 3.70 kg on a frictionless plane inclined at angle θ = 30.0° is connected by a cord over a massless, frictionless pulley to a second block of mass *m*_{2}^{ }= 2.30 kg (Fig. 5-52). Find**(a)** the magnitude of the acceleration of each block,**(b) **the direction of the acceleration of the hanging block,** ****(c) **the tension in the cord.

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A sphere of mass 3.0×10^{-4 }kg is suspended from a cord. A steady horizontal breeze pushes the sphere so that the

cord makes a constant angle of 37° with the vertical. Find**(a)** the push magnitude and**(b)** the tension in the cord.

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The speed of a bullet is measured to be 640m/s as the bullet emerges from a barrel of length 1.20m. Assuming constant acceleration, find the time that the bullet spends in the barrel after it is fired.

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A jumbo jet must reach a speed of 360km/h on the runway for takeoff. What is the lowest constant acceleration needed for takeoff from a 1.80km runway?

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The head of a rattlesnake can accelerate at 50m/s^{2} in striking a victim. If a car could do as well, how long would it take to reach a speed of 100km/h from rest?

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A motorcycle is moving at 30 m/s when the rider applies the brakes, giving the motorcycle a constant deceleration. During the 3.0 s interval immediately after braking begins, the speed decreases to 15 m/s. What distance does the motorcycle travel from the instant braking begins until the motorcycle stops?

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If a baseball pitcher throws a fastball at a horizontal speed of 160km/h, how long does the ball take to reach home plate 18.4m away?

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A stone is thrown vertically upward. On its way up it passes point A with speed *v*, and point B, 3.00 m higher than A, with speed ½*v*. Calculate**(a)** the speed *v *and**(b)** the ma*x*imum height reached by the stone above point B.

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A motorcyclist who is moving along an *x *axis directed toward the east has an acceleration given by *a* *= *(6.1 − 1.2*t*) m/s^{2} for 0 ≤ *t* ≤ 6.0 s. At *t* *= *0, the velocity and position of the cyclist are 2.7 m/s and 7.3 m.**(a)** What is the ma*x*imum speed achieved by the cyclist?**(b)** What total distance does the cyclist travel between *t **=* 0 and 6.0 s?

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A stone is dropped into a river from a bridge 43.9m above the water. Another stone is thrown vertically down 1.00s after the first is dropped. The stones strike the water at the same time.

What is the initial speed of the second stone?

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A key falls from a bridge that is 45m above the water. It falls directly into a model boat, moving with constant velocity, that is 12m from the point of impact when the key is released. What is the speed of the boat?

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A hoodlum throws a stone vertically downward with an initial speed of 12.0m/s from the roof of a building, 30.0m above the ground.** ****(a)** How long does it take the stone to reach the ground? **(b)** What is the speed of the stone at impact?

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A car traveling 56.0 km/h is 24.0 m from a barrier when the driver slams on the brakes. The car hits the barrier 2.00 s later.**(a)** What is the magnitude of the car’s constant acceleration before impact?**(b)** How fast is the car traveling at impact?

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On a dry road, a car with good tires may be able to brake with a constant deceleration of 4.92 m/s. **(a)** How long does such a car, initially traveling at 24.6 m/s, take to stop?**(b)** How far does it travel in this time? **(c)** Graph *x * versus *t *and *v* versus *t *for the deceleration.

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