1. A skydiver is falling straight down, along the negative y o During the initial part of the fall, her speed increases from 16 to 28 m/s in 1.5 s. o Later, her parachute opens, and her speed decreases from 48 to 26 m/s in 11 s. o In both instances, determine the magnitude and direction of her average acceleration. direction. 2. A projectile is launched from and returns to ground level. Air resistance is absent. The horizontal range of the projectile is measured to be R = 175 m, and the horizontal component of the launch velocity is Vox = 25 m/s. Find the vertical component Voy of the launch velocity. 3. When chasing a hare along a flat stretch of ground, a greyhound leaps into the air at a speed of 10.0 m/s, at an angle of 31.0 degrees above the horizontal. o What is the range of his leap and o For how much time is he in the air?

A car is moving along a straight road with an initial velocity of v 11 m/s and an acceleration, a=8 m/s. What is the distance traveled (in m) after t=2 s? A. 152 В. 38 C. None D. 114 E. 76

Two 47. identical pellet guns are fired simultaneously from the edge of a cliff. These guns impart an initial speed of 30.0 m/s to each pellet. Gun A is fired straight upward, with the pellet going up and then falling back down, eventually hitting the ground beneath the cliff. Gun B is fired straight downward. In the absence of air resistance, how long after pellet B hits the ground does pellet A hit the ground? 48. mmh An astronaut on a distant planet wants to determine its accel- eration due to gravity. The astronaut throws a rock straight up with a ve- locity of +15 m/s and measures a time of 20.0 s before the rock returns to his hand. What is the acceleration (magnitude and direction) due to gravity on this planet? I 52. A ball is thrown straight upward. At 4.00 m above its launch point, the ball's speed is one-half its launch speed. What maximum height above its launch point does the ball attain? 53. ssm From her bedroom window a girl drops a water-filled balloon to the ground,…

Answer the ff: 1. A juggler throws a bowling pin straight up with an initialspeed of 8.20 m/s. How much time elapses until the bowling pinreturns to the juggler’s hand? 2. A car travels in the +x-direction on a straight and levelroad. For the first 4.00 s of its motion, the average velocity of thecar is vav-x = 6.25 m/s. How far does the car travel in 4.00 s?

Component Method: With your calculator, determine the x and y components of F1 and F2. Remember that Fx = Fcos θ and Fy = F sin θ. Find the x and y components of the resultant from the sum of x and y components. Draw a right triangle with x and y components as sides, and the hypotenuse representing the resultant. Calculate the magnitude of the resultant from the square root of (Rx2 + Ry2). Calculate the direction of the resultant by using θ R = tan-1 (Ry/Rx).

2. At time t = 0, the vectors E andB are given by E vectors, Eo and Bo are fixed and orthogonal. The equations of motion are E, and B = Bo, where the unit %3D dE E +Bx E- dr dB B.+ Ex B. dt Find E and B at a general time t. showing that after a long time the directions of E and B have almost interchanged.

3. You wake up in a strange room, with opaque walls, and no visible doors or windows. you drop a ball from a height of 1.50 m, and observe that it hits the floor 0.277 s after you drop it. In this case, you suspect you are in deep space, far from any planet or star, and that your rocket is accelerating due to the push of its own engines under the floor. In this case, what must the acceleration of your rocket be?     29.3 m/s^2     58.7 m/s^2     39.1 m/s^2     19.5 m/s^2

A model rocket is fired straight up from the top of a 50-m tall building. The rocket has only enough fuel to burn for 2s. But while the rocket engine is burning fuel, it produces an upward acceleration of 50 m/s^2. After the fuel supply is exhausted, the rocket is in free fall and just misses the edge of a building as it falls back to the ground. Ignoring air resistance, calculate a. the height above the ground and the velocity of the rocket when its fuel runs out. b. the maximum height of the rocket c. the time the rocket is in the air. d. the rocket's velocity the moment before it hits the ground.

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A particle P is moving on the x axis and its acceleration a ms-²,t seconds after a given instant, is given by a = 6t - 18 The particle is initially at the origin O, moving with a speed of 15 m/s in the positive x direction. Determine the times when P is instantaneously at rest (v=0m/s). a. t = ls, 5s b. t=3s, 7s O c. t = 2s, 5s O d. t=2s, 4s O e.t=1s, 7s