Kinematics Questions and Answers

A car is moving at a constant speed of 10 m/s when the driver presses down on the gas pedal and accelerates for 13 s with an acceleration of 1.8 m/s². What is the average speed of the car during the period? Answer in units of m/s.

A car moving with an initial velocity of 35.4 m/s slows down at a constant rate of -1.1 m/s². (a) What is its velocity after 9 seconds of deceleration? (b) What distance does the car cover in this time?

A block of mass 2kg is projected upwards with speed 10 m/s & stops momentarily at height of 4m & returns with speed of 8 m/s. (consider air resistance is present and take g=10m/s² Work done by air resistance in ascending motion is -20 J Work done by air resistance in descending motion is -16 J Total work done by air resistance is 38 J Total work done by air resistance is -38 J

A water balloon is dropped from a height of 144 feet. a. After how many seconds does the water balloon hit the ground? The water balloon hits the ground after __ seconds. b. Suppose the initial height is adjusted by k feet. How does this affect part (a)? When k __ 0, the water balloon will take more than __ seconds to hit the ground. When k __ 0, the water balloon will take less than __ seconds to hit the ground

A Nile cruise ship takes 20.8 h to go upstream from Luxor to Aswan, a distance of 255 km, and 19.2 h to make the return trip downstream. Assuming the ship's speed relative to the water is the same in both cases, calculate the speed of the current in the Nile in km/h.

A 6.0-kg box slides along a horizontal frictionless rail of a packing machine with a speed of 1.4 m/s. The box is stopped at the end of the rail by a spring with k=420 N/m attached to a wall. What is the maximum compression of the spring when the box collides with it? 0.010 m 0.17 m 0.14 m 0.00056 m 0.020 m

During a walk on the Moon, an astronaut accidentally drops his camera over a cliff. It leaves his hands with zero speed, and after 2.00 s it attains a velocity of 7.50 m/s downward. How far has the camera fallen after 8.40 s?

A car is travelling along a highway with a speed of 25 m/s when the driver sees an obstruction 1.80 10² m directly ahead. It takes the driver 0.80 s to react and begin braking. (a) How far does the car travel before it begins to slow down? (b) How long will it take the car to stop once the brakes are applied, provided the car stops just before the obstruction? (c) What is the value of the acceleration of the car if it just misses hitting the obstruction? Assume the acceleration is uniform.

An object is moving along the x-axis and its position varies in time according to the expression x = (3.00 m/s²)t², where x is in meters and t is in seconds. (a) Determine its position (in m) at t = 4.00 s. (b) Determine its position (in m) at t = (4.00 s) + At. (Use the following as necessary: At. Do not include units in your answer.) (c) Evaluate the limit of. as At approaches zero to find the velocity (in m/s) at t = 4.00 s.

A cannon is aimed across Bottomless Gorge at an angle of 22.6° above the horizontal. The mouth of the cannon is 1.00 m above the ground. It shoots a ball whose velocity upon leaving the canon is 130 m/s. a. What are the horizontal and vertical components of the initial velocity of the ball? b. What is the velocity of the ball after 2.00 s? (don't forget angle to horizontal) c. If the ball strikes the other side of the gorge 55.0 m below the mouth of the cannon, how wide is Bottomless Gorge? (1320 m)

Human reaction times are worsened by alcohol. How much further (in feet) would a drunk driver's car travel before he hits the brakes than a sober driver's car? Assume that both are initially traveling at 50.0 mi/h and their cars have the same acceleration while slowing down, and that the sober driver takes 0.33 s to hit the brakes in a crisis, while the drunk driver takes 1.0 s to do so. (5280 ft = 1 mi)

A race car is traveling at 76 m/sec. The race car then slows down at a rate of -9 m/sec² for 4 seconds. What is the new speed of the race car after 4 seconds? A. 40 m/sec B. 50 m/sec C. 60 m/sec D. 70 m/sec

A marble rolled down an inclined ramp with an acceleration of 0.500 m/s² for 7.00 seconds will travel meters from the point where it was released. A. 12.3 B. 24.5 C. 1.80 D. None of the above

A soccer ball is released from rest at the top of a grassy incline. After 6.4 seconds the ball has rolled 91 m with constant acceleration, and 1.0 s later it reaches the bottom of the incline. (a) What was the ball's acceleration? (b) How long was the incline?>

A basketball dropped from the roof of a three-story building falls to the ground. Ignoring air resistance, sketch the motion diagram for this motion, including approximate representations of the position versus time, velocity versus time, and acceleration versus time graphs for this motion. Include axes labels, appropriate numbers, nd units for each graph. Upload an image of the sketches and explain your sketches in words in the panels below.

A car is moving with a speed of 32.0 m/s. The driver sees an accident ahead and slams on the brakes, causing the car to slow down with a uniform acceleration of magnitude 3.50 m/s2. How far does the car travel after the driver put on the brakes until it comes to a stop? (show your work)

A myosin molecule "walks" along a one-dimensional actin track inside of a cell. The myosin molecule has the following displacements in the given time intervals: Ax₁ = 4.5 um in 4 s Ax2 = -3.7 μm in 10 s Ax3 = 1.9 μm in 5 s What was the average speed of the myosin molecule for the entire motion?

Two cyclists who weigh the same and have identical bicycles ride up the same mountain, both starting at the same time. Joe rides straight up the mountain, and Bob rides up the longer road that has a lower grade. Joe gets to the top before Bob. Ignoring friction and wind resistance, which one of the following statements is true? A. The amount of work done by Joe is greater than the amount of work done by Bob, and the average power exerted by Joe is greater than that of Bob. B. The average power exerted by Bob and Joe was the same, but Joe exerted more work in getting there. C. Bob and Joe exerted the same amount of work, and the average power of each cyclist was also the same. D. The amount of work done by Joe is equal to the amount of work done by Bob, but the average power exerted by Joe is greater than that of Bob.

A coal-burning electrical generating plant emits sulfur dioxide into the surrounding air. The concentration C(a), in parts per million, is approximately given by the function where is the distance away from the plant in miles. The instantaneous rate of change of the sulfur dioxide concentration: (A) 4 miles from the plant = (B) 8 miles from the plant =

On the first play of a football game, the kicker kicks the ball with a speed of 30 m/s, and the ball travels a distance of 55 m (about 60 yd). There are two possible angles, relative to the horizontal, that the ball could have been kicked. What is the smallest of those two angles?

A locomotive is pulling three train cars along a level track with a force of 100,000 N. The car next to the locomotive has a mass of 80,000 kg, the next one, 50,000 kg, and the last one, 70,000 kg. You can neglect the friction on the cars being pulled. (a) What is the magnitude of the force between that the 80,000-kg car exerts on the 50,000-kg car? (b) What is the magnitude of the force that the 50,000-kg car exerts on the 70,000-kg car?

You are taking flying lessons from an experienced pilot. You and the pilot are up in the plane, with you in the pilot seat. The control tower radios the plane, saying that, while you have been airborne, a 33.0 mi/h crosswind has arisen, with the direction of the wind perpendicular to the runway on which you plan to land. The pilot tells you that your normal airspeed as you land will be 91.0 mi/h relative to the ground. This speed is relative to the air, in the direction in which the nose of the airplane points. He asks you to determine the angle (in degrees) at which the aircraft must be "crabbed," that is, the angle between the centerline of the aircraft and the centerline of the runway that will allow the airplane's velocity relative to the ground to be parallel to the runway.

A car stopped at the traffic light and when the light turns green the car starts from rest with an acceleration of 2.5 m/s², a truck traveling at constant velocity of 40 Km/h passes the car. Where from the traffic light will the car catch up the truck?

A model rocket is launched straight upward with an initial speed of 44.0 m/s. It accelerates with a constant upward acceleration of 3.00 m/s² until its engines stop ot an altitude of 190 m. (a) What can you say about the motion of the rocket after its engines stop? (b) What is the maximum height reached by the rocket? (c) How long after liftoff does the rocket reach its maximum height? (d) How long is the racket in the air?

The tape in a videotape cassette has a total length 196 m and can play for 1.7 h. As the tape starts to play, the full reel has an outer radius of 43 mm and an inner radius of 12 mm. At some point during the play, both reels will have the same angular speed. What is this common angular speed? Answer in units of rad/s. The driver of a car traveling at 23.7 m/s ap- plies the brakes and undergoes a constant deceleration of 2.18 m/s². How many revolutions does each tire make before the car comes to a stop, assuming that the car does not skid and that the tires have radii of 0.34 m?

A box of mass 23 kg is at rest on a horizontal frictionless surface. A constant horizontal force of magnitude F then acts on the box, accelerating it to the right. You observe that it takes the box 7.5 seconds to travel 38 meters. What is the magnitude of the force F?

A golfer drives a golf ball 214 m [E] of the tee, then hits it 96 m [28° N of E], and finally putts the ball 12 m [25° S of E]. Determine the displacement from the tee needed to get a hole-in-one using the component method of vector addition.

A car is traveling north at 17.7 m/s. After 12 s its velocity is 141 m/s in the same direction. Find the magnitude and direction of the car's average acceleration. A. 2.7 m/s2, north B. 2.7 m/s2, south C. 0.30 m/s², south D. 0.30 m/s2, north

A home run is hit in such a way that the baseball just clears a wall 16.0 m high, located 110 m from home plate. The ball is hit at an angle of 31.0° to the horizontal, and air resistance is negligible. (Assume that the ball is hit at a height of 1.0 m above the ground.) (a) Find the initial speed of the ball. (b) Find the time it takes the ball to reach the wall. (c) Find the velocity components of the ball when it reaches the wall. Find the speed of the ball when it reaches the wall.

A hockey puck slides off the edge of a horizontal platform with an initial velocity of 28.0 m/shorizontally in a city where the acceleration due to gravity is 9.81 m/s2. The puck experiences no significant air resistance as it falls. The height of the platform above the ground is 2.00 m. What is the angle below the horizontal of the velocity of the puck just before it hits the ground? A. 12.6° B. 77.2° C. 31.8° D. 12.8° E. 72.6°

A car of mass 1100 kg that is traveling at 27 m/s starts to slow down and comes to a complete stop in 578 m. What is the magnitude of the average braking force acting on the car? A. 690 N B. 550 N C. 410 N D. 340 N

While jogging around town, you travel along the following displacements in succession: 1.5 km due north, then 2.5 km due northeast, then 3.0 km due west. What is the magnitude of your final displacement from your starting position, in kilometers?

At what angle with horizontal should a body be projected with a velocity 24 ms-¹ just to pass over the obstacle 14 m high at a distance of 24 m? [Take g = 10 ms-²] (A) tan-¹(19/5) (B) 45° (C) tan-¹ (2) (D) 60°

A horizontal rope is tied to a 90 kg box on frictionless ice. What is the tension in the rope if the box is at rest? E What is the tension in the rope if the box moves at a steady 6.0 m/s?

A 50 kg box hangs from a rope. What is the tension in the rope if the box moves up at a steady 5.0 m/s? What is the tension in the rope if the box has vy= 5.0 m/s and is slowing down at 5.0 m/s² ?

In t-ball, young players use a bat to hit a stationary ball off a stand. The 140 g ball has about the same mass as a baseball, but it is larger and softer. In one hit, the ball leaves the bat at 12 m/s after being in contact with the bat for 2.0 ms. Assume constant acceleration during the hit. What is the acceleration of the ball?

Imagine holding a basketball in both hands, throwing it straight up as high as you can, and then catching it when it falls. At which points in time does a zero net force act on the ball? Ignore air resistance. Check all that apply. when you hold the ball still in your hands before it is thrown just after the ball first leaves your hands when you hold the ball still in your hands after catching it at the instant the ball reaches its highest point at the instant the falling ball hits your hands

A golfer hits a shot to a green that is elevated 3.10 m above the point where the ball is struck. The ball leaves the club at a speed of 17.2 m/s at an angle of 33.0° above the horizontal. It rises to its maximum height and then falls down to the green. Ignoring air resistance, find the speed of the ball just before it lands.

Ocean waves lap against a deserted beach once every 5 seconds. If there are about 10 meters between each ocean wave, what is the speed of the ocean waves? Select one: a.2 m/s b. 200 m/s c. 1000 m/s d. 50 m/s

The equation d=1/2 a t^2, that is, the distance traveled is equal to one half the acceleration times the square of the time taken for the trip, is incorrect if the trip began with a nonzero velocity. True - False

In a ballistics test, a bullet moving horizontally with a speed of 500 m/s strikes a sandbag and penetrates a distance of 10.0 cm. (a) What is the magnitude of the average acceleration of the bullet in the sandbag? (b) How many milliseconds does it take the bullet to come to rest in the sandbag?

Arthur and Betty start walking toward each other when they are 100 m apart. Arthur has a speed of 3.0 m/s and Betty has a speed of 2.0 m/s. How long does it take for them to meet? 1.

Assuming equal rates of uniform acceleration in both cases, how much further would you travel if braking from 56 mi/h to rest than from 28 mi/h? 3.2 times farther 5.2 times farther 4 times farther 4.8 times farther

A train locomotive is pulling two cars of the same mass behind it, Fig. 4-51. Determine the ratio of the tension in the coupling (think of it as a cord) between the locomotive and the first car (FT₁), to that between the first car and the second car (FT2), for any nonzero acceleration of the train.

An object is moving with constant non-zero acceleration in the +x direction. The velocity versus time graph of this object is a horizontal straight line. a vertical straight line. a straight line making an angle with the time axis. a parabolic curve.

A toy rocket is launched vertically from ground level at time t = 0.00 s. The rocket engine provides constant upward acceleration during the burn phase. At the instant of engine burnout, the rocket has risen to 81 m and acquired an upward velocity of 40 m/s. The rocket continues to rise with insignificant air resistance in unpowered flight, reaches maximum height, and falls back to the ground. The upward acceleration of the rocket during the burn phase is closest to 9.0 m/s² 9.9 m/s² 8.7 m/s². 9.6 m/s². 9.3 m/s².

A ball is thrown up from the top of a building 55.0 m high. It rises to a maximum height of 20.0 m above the roof. (a) When does it land on the ground below? (b) At what velocity does it land? (c) When is it 20.0 m below the roof?

A rescue plane wants to drop supplies to isolated mountain climbers on a rocky ridge 235 m below. If the plane is traveling horizontally with a speed of 250 km/h (69.4 m/s), how far in advance of the recipients (horizontal distance) must the goods be dropped (Fig. 3-38)?

A ball is dropped from the roof of a tall building and students in a physics class are asked to sketch a motion diagram for this situation. A student submits the diagram shown in Figure Q1.4. Is the diagram cor- rect? Explain.

Graphing calculator allowed. The position function of a particle in rectilinear motion is given by the equation a. Sketch graphs of the position, velocity, and acceleration graphs for the interval 0 ≤ t ≤ 16. Label and mark the axes. b. Determine, to the thousandths place, the value of t at which the particle reverses direction. Explain. C. Find the position, velocity, and acceleration at the t value found in part b. d. Determine the time intervals on which the particle is speeding up and when it is slowing down. Explain. e. Determine when the particle has its maximum and minimum velocities.