Question: A potter’s wheel moves uniformly from

> A billiard ball rolling across a table at 1.50 m/s makes a headon elastic collision with an identical ball. Find the speed of each ball after the collision (a) When the second ball is initially at rest, (b) When the second ball is moving toward the first

> A 25.0-g object moving to the right at 20.0 cm/s overtakes and collides elastically with a 10.0-g object moving in the same direction at 15.0 cm/s. Find the velocity of each object after the collision.

> A space probe, initially at rest, undergoes an internal mechanical malfunction and breaks into three pieces. One piece of mass m1 = 48.0 kg travels in the positive x - direction at 12.0 m/s, and a second piece of mass m2 = 62.0 kg travels in the xy-plane

> A tennis ball of mass 57.0 g is held just above a basketball of mass 590 g. With their centers vertically aligned, both balls are released from rest at the same time, falling through a distance of 1.20 m, as shown in Figure P6.45. (a) Find the magnitude

> A 1200-kg car traveling initially with a speed of 25.0 m/s in an easterly direction crashes into the rear end of a 9000-kg truck moving in the same direction at 20.0 m/s (Fig. P6.44). The velocity of the car right after the collision is 18.0 m/s to the e

> A 12.0-g bullet is fired horizontally into a 100-g wooden block that is initially at rest on a frictionless horizontal surface and connected to a spring having spring constant 150 N/m. The bullet becomes embedded in the block. If the bullet– block system

> An bullet of mass m = 8.00 g is fired into a block of mass M = 250 g that is initially at rest at the edge of a table of height h = 1.00 m (Fig. P6.42). The bullet remains in the block, and after the impact the block lands d = 2.00 m from the bottom of t

> A 0.030-kg bullet is fired vertically at 200 m/s into a 0.15-kg baseball that is initially at rest. How high does the combined bullet and baseball rise after the collision, assuming the bullet embeds itself in the ball?

> Two shuffleboard disks of equal mass, one orange and the other green, are involved in a perfectly elastic glancing collision. The green disk is initially at rest and is struck by the orange disk moving initially to the right at 5.00 m/s as in Figure P6.4

> A ball is falling toward the ground. Which of the following statements are false? (a) The force that the ball exerts on Earth is equal in magnitude to the force that Earth exerts on the ball. (b) The ball undergoes the same acceleration as Earth. (c) The

> In a Broadway performance, an 80.0-kg actor swings from a 3.75-m-long cable that is horizontal when he starts. At the bottom of his arc, he picks up his 55.0-kg costar in an inelastic collision. What maximum height do they reach after their upward swing?

> A cue ball traveling at 4.00 m/s makes a glancing, elastic collision with a target ball of equal mass that is initially at rest. The target ball deflects the cue ball so that its subsequent motion makes an angle of 30.0° with respect to its original dire

> Consider the ballistic pendulum device discussed in Example 6.5 and illustrated in Figure 6.13. (a) Determine the ratio of the momentum immediately after the collision to the momentum immediately before the collision. (b) Show that the ratio of the kinet

> A railroad car of mass M moving at a speed v1 collides and couples with two coupled railroad cars, each of the same mass M and moving in the same direction at a speed v2. (a) What is the speed vf of the three coupled cars after the collision in terms of

> A railroad car of mass 2.00 x 104 kg moving at 3.00 m/s collides and couples with two coupled railroad cars, each of the same mass as the single car and moving in the same direction at 1.20 m/s. (a) What is the speed of the three coupled cars after the c

> A 75.0-kg ice skater moving at 10.0 m/s crashes into a stationary skater of equal mass. After the collision, the two skaters move as a unit at 5.00 m/s. Suppose the average force a skater can experience without breaking a bone is 4500 N. If the impact ti

> Gayle runs at a speed of 4.00 m/s and dives on a sled, initially at rest on the top of a frictionless, snow- covered hill. After she has descended a vertical distance of 5.00 m, her brother, who is initially at rest, hops on her back, and they continue d

> An archer shoots an arrow toward a 3.00 x 102 - g target that is sliding in her direction at a speed of 2.50 m/s on a smooth, slippery surface. The 22.5-g arrow is shot with a speed of 35.0 m/s and passes through the target, which is stopped by the impac

> A man of mass m1 = 70.0 kg is skating at v1 = 8.00 m/s behind his wife of mass m2 = 50.0 kg, who is skating at v2 = 4.00 m/s. Instead of passing her, he inadvertently collides with her. He grabs her around the waist, and they maintain their balance. (a)

> A pail of water is rotated in a vertical circle of radius 1.00 m. (a) What two external forces act on the water in the pail? (b) Which of the two forces is most important in causing the water to move in a circle? (c) What is the pail’s minimum speed at t

> An object moves in a circular path with constant speed v. Which of the following statements is true concerning the object? (a) Its velocity is constant, but its acceleration is changing. (b) Its acceleration is constant, but its velocity is changing. (c)

> A woman places her briefcase on the backseat of her car. As she drives to work, the car negotiates an unbanked curve in the road that can be regarded as an arc of a circle of radius 62.0 m. While on the curve, the speed of the car is 15.0 m/s at the inst

> A snowboarder drops from rest into a halfpipe of radius R and slides down its frictionless surface to the bottom (Fig. P7.28). Show that (a) The snowboarder’s speed at the bottom of the halfpipe is v = √2gR (b) The sno

> An air puck of mass m1 = 0.25 kg is tied to a string and allowed to revolve in a circle of radius R = 1.0 m on a frictionless horizontal table. The other end of the string passes through a hole in the center of the table, and a mass of m2 = 1.0 kg is tie

> A space habitat for a long space voyage consists of two cabins each connected by a cable to a central hub as shown in Figure P7.26. The cabins are set spinning around the hub axis, which is connected to the rest of the spacecraft to generate artificial g

> A 50.0-kg child stands at the rim of a merry-go-round of radius 2.00 m, rotating with an angular speed of 3.00 rad/s. (a) What is the magnitude of the child’s centripetal acceleration? (b) What is the magnitude of the minimum force between her feet and t

> A sample of blood is placed in a centrifuge of radius 15.0 cm. The mass of a red blood cell is 3.0 x 10-16 kg, and the magnitude of the force acting on it as it settles out of the plasma is 4.0 x 10-11 N. At how many revolutions per second should the cen

> A certain light truck can go around a flat curve having a radius of 150 m with a maximum speed of 32.0 m/s. With what maximum speed can it go around a curve having a radius of 75.0 m?

> A 40.0-kg child swings in a swing supported by two chains, each 3.00 m long. The tension in each chain at the lowest point is 350 N. Find (a) The child’s speed at the lowest point and (b) The force exerted by the seat on the child at the lowest point. (I

> A 55.0-kg ice skater is moving at 4.00 m/s when she grabs the loose end of a rope, the opposite end of which is tied to a pole. She then moves in a circle of radius 0.800 m around the pole. (a) Determine the force exerted by the horizontal rope on her ar

> Human centrifuges are used to train military pilots and astronauts in preparation for high-g maneuvers. A trained, fit person wearing a g - suit can withstand accelerations up to about 9g (88.2 m/s2) without losing consciousness. (a) If a human centrifug

> A racetrack is constructed such that two arcs of radius 80 m at â’¶ and 40 m at â’· are joined by two stretches of straight track as in Figure 7.8. In a particular trial run, a driver travels at a constant speed of 50 m/

> One end of a cord is fixed and a small 0.500-kg object is attached to the other end, where it swings in a section of a vertical circle of radius 2.00 m, as shown in Figure P7.19. When θ = 20.0°, the speed of the object is 8.00 m/s

> An adventurous archeologist (m = 85.0 kg) tries to cross a river by swinging from a vine. The vine is 10.0 m long, and his speed at the bottom of the swing is 8.00 m/s. The archeologist doesn’t know that the vine has a breaking strength of 1000 N. Does h

> (a) What is the tangential acceleration of a bug on the rim of a 10.0-in.-diameter disk if the disk accelerates uniformly from rest to an angular velocity of 78.0 rev/min in 3.00 s? (b) When the disk is at its final speed, what is the tangential velocity

> It has been suggested that rotating cylinders about 10 mi long and 5.0 mi in diameter be placed in space and used as colonies. What angular speed must such a cylinder have so that the centripetal acceleration at its surface equals the free-fall accelerat

> A car initially traveling eastward turns north by traveling in a circular path at uniform speed as shown in Figure P7.15. The length of the arc ABC is 235 m, and the car completes the turn in 36.0 s. (a) Determine the car’s speed. (b) W

> An electric motor rotating a workshop grinding wheel at a rate of 1.00 x 102 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 2.00 rad/s2. (a) How long does it take for the grinding wheel to stop? (b) Th

> A rotating wheel requires 3.00 s to rotate 37.0 revolutions. Its angular velocity at the end of the 3.00-s interval is 98.0 rad/s. What is the constant angular acceleration (in rad/s2) of the wheel?

> A child is practicing for a BMX race. His speed remains constant as he goes counterclockwise around a level track with two nearly straight sections and two nearly semicircular sections, as shown in the aerial view of Figure CQ7.12. (a) What are the direc

> A car initially traveling at 29.0 m/s undergoes a constant negative acceleration of magnitude 1.75 m/s2 after its brakes are applied. (a) How many revolutions does each tire make before the car comes to a stop, assuming the car does not skid and the tire

> A car of mass m follows a truck of mass 2m around a circular turn. Both vehicles move at speed v. (a) What is the ratio of the truck’s net centripetal force to the car’s net centripetal force? (b) At what new speed vtruck will the net centripetal force a

> When the merry-go-round of Quick Quiz 7.4 is rotating at a constant angular speed, Andrea’s tangential speed is (a) Twice Chuck’s (b) The same as Chuck’s (c) Half of Chuck’s (d) Impossible to determine. Data From Quick Quiz 7.4: Andrea and Chuck are rid

> The diameters of the main rotor and tail rotor of a singleengine helicopter are 7.60 m and 1.02 m, respectively. The respective rotational speeds are 450 rev/min and 4138 rev/ min. Calculate the speeds of the tips of both rotors. Compare these speeds wit

> Describe the path of a moving object in the event that the object’s acceleration is constant in magnitude at all times and (a) Perpendicular to its velocity; (b) Parallel to its velocity.

> A bicyclist starting at rest produces a constant angular acceleration of 1.60 rad/s2 for wheels that are 38.0 cm in radius. (a) What is the bicycle’s linear acceleration? (b) What is the angular speed of the wheels when the bicyclist reaches 11.0 m/s? (c

> Because of Earth’s rotation about its axis, you weigh slightly less at the equator than at the poles. Explain.

> A dentist’s drill starts from rest. After 3.20 s of constant angular acceleration, it turns at a rate of 2.51 x 104 rev/min. (a) Find the drill’s angular acceleration. (b) Determine the angle (in radians) through which the drill rotates during this perio

> Objects moving along a circular path have a centripetal acceleration provided by a net force directed towards the center. Identify the force(s) providing the centripetal acceleration in each of these cases: (a) A planet in circular orbit around its sun;

> A bicycle tire is spinning clockwise at 2.50 rad/s. During a time period Δt = 1.25 s, the tire is stopped and spun in the opposite (counterclockwise) direction, also at 2.50 rad/s. Calculate (a) The change in the tire’s angular velocity Δw and (b) The ti

> The tires on a new compact car have a diameter of 2.0 ft and are warranted for 60000 miles. (a) Determine the angle (in radians) through which one of these tires will rotate during the warranty period. (b) How many revolutions of the tire are equivalent

> A model airplane of mass 0.750 kg flies with a speed of 35.0 m/s in a horizontal circle at the end of a 60.0-m control wire as shown in Figure P7.60a. The forces exerted on the airplane are shown in Figure P7.60b; the tension in the control wire, Î

> In Robert Heinlein’s The Moon Is a Harsh Mistress, the colonial inhabitants of the Moon threaten to launch rocks down onto Earth if they are not given independence (or at least representation). Assuming a gun could launch a rock of mass m at twice the lu

> A roller coaster travels in a circular path. (a) Identify the forces on a passenger at the top of the circular loop that cause centripetal acceleration. Show the direction of all forces in a sketch. (b) Identify the forces on the passenger at the bottom

> Because of Earth’s rotation about its axis, a point on the equator has a centripetal acceleration of 0.034 0 m/s2, whereas a point at the poles has no centripetal acceleration. (a) Show that, at the equator, the gravitational force on an object (the obje

> Keratinocytes are the most common cells in the skin’s outer layer. As these approximately circular cells migrate across a wound during the healing process, they roll in a way that reduces the frictional forces impeding their motion. (a) Given a cell body

> A car moves at speed v across a bridge made in the shape of a circular arc of radius r. (a) Find an expression for the normal force acting on the car when it is at the top of the arc. (b) At what minimum speed will the normal force become zero (causing t

> A 0.400-kg pendulum bob passes through the lowest part of its path at a speed of 3.00 m/s. (a) What is the tension in the pendulum cable at this point if the pendulum is 80.0 cm long? (b) When the pendulum reaches its highest point, what angle does the c

> The Solar Maximum Mission Satellite was placed in a circular orbit about 150 mi above Earth. Determine (a) The orbital speed of the satellite and (b) The time required for one complete revolution.

> The dung beetle is known as one of the strongest animals for its size, often forming balls of dung up to 10 times their own mass and rolling them to locations where they can be buried and stored as food. A typical dung ball formed by the species K. nigro

> An athlete swings a 5.00-kg ball horizontally on the end of a rope. The ball moves in a circle of radius 0.800 m at an angular speed of 0.500 rev/s. What are (a) The tangential speed of the ball and (b) Its centripetal acceleration? (c) If the maximum te

> Suppose an alien civilization has a space station in circular orbit around its home planet. The station’s orbital radius is twice the planet’s radius. (a) If an alien astronaut has weight w just before launch from the surface, will she be weightless when

> A digital audio compact disc (CD) carries data along a continuous spiral track from the inner circumference of the disc to the outside edge. Each bit occupies 0.6 mm of the track. A CD player turns the disc to carry the track counterclockwise above a len

> One method of pitching a softball is called the “windmill” delivery method, in which the pitcher’s arm rotates through approximately 360° in a vertical plane before the 198- gram ball is released at the lowest point of the circular motion. An experienced

> Neutron stars are extremely dense objects that are formed from the remnants of supernova explosions. Many rotate very rapidly. Suppose the mass of a certain spherical neutron star is twice the mass of the Sun and its radius is 10.0 km. Determine the grea

> (a) One of the moons of Jupiter, named Io, has an orbital radius of 4.22 x 108 m and a period of 1.77 days. Assuming the orbit is circular, calculate the mass of Jupiter. (b) The largest moon of Jupiter, named Ganymede, has an orbital radius of 1.07 x 10

> A synchronous satellite, which always remains above the same point on a planet’s equator, is put in circular orbit around Jupiter to study that planet’s famous red spot. Jupiter rotates once every 9.84 h. Use the data

> A comet has a period of 76.3 years and moves in an elliptical orbit in which its perihelion (closest approach to the Sun) is 0.610 AU. Find (a) The semimajor axis of the comet and (b) An estimate of the comet’s maximum distance from the Sun, both in astr

> A 600-kg satellite is in a circular orbit about Earth at a height above Earth equal to Earth’s mean radius. Find (a) The satellite’s orbital speed, (b) The period of its revolution, and (c) The gravitational force acting on it.

> A satellite of Mars, called Phoebus, has an orbital radius of 9.4 x 106 m and a period of 2.8 x 104 s. Assuming the orbit is circular, determine the mass of Mars.

> An artificial satellite circling the Earth completes each orbit in 110 minutes. (a) Find the altitude of the satellite. (b) What is the value of g at the location of this satellite?

> A satellite is in a circular orbit around the Earth at an altitude of 2.80 x 106 m. Find (a) The period of the orbit, (b) The speed of the satellite, and (c) The acceleration of the satellite.

> Convert (a) 47.0° to radians, (b) 12.0 rad to revolutions, and (c) 75.0 rpm to rad/s.

> Two objects attract each other with a gravitational force of magnitude 1.00 x 10-8 N when separated by 20.0 cm. If the total mass of the objects is 5.00 kg, what is the mass of each?

> A projectile is fired straight upward from the Earth’s surface at the South Pole with an initial speed equal to one third the escape speed. (a) Ignoring air resistance, determine how far from the center of the Earth the projectile travels before stopping

> Use the data of Table 7.3 to find the point between Earth and the Sun at which an object can be placed so that the net gravitational force exerted by Earth and the Sun on that object is zero. Table 7.3:

> Objects with masses of 200. kg and 500. kg are separated by 0.400 m. (a) Find the net gravitational force exerted by these objects on a 50.0-kg object placed midway between them. (b) At what position (other than infinitely remote ones) can the 50.0-kg ob

> After the Sun exhausts its nuclear fuel, its ultimate fate may be to collapse to a white dwarf state. In this state, it would have approximately the same mass as it has now, but its radius would be equal to the radius of Earth. Calculate (a) The average

> A coordinate system (in meters) is constructed on the surface of a pool table, and three objects are placed on the table as follows: a 2.0-kg object at the origin of the coordinate system, a 3.0-kg object at (0, 2.0), and a 4.0-kg object at (4.0, 0). Fin

> The International Space Station has a mass of 4.19 x 105 kg and orbits at a radius of 6.79 x 106 m from the center of Earth. Find (a) The gravitational force exerted by Earth on the space station, (b) The space station’s gravitational potential energy, a

> (a) Find the magnitude of the gravitational force between a planet with mass 7.50 x 1024 kg and its moon, with mass 2.70 x 1022 kg, if the average distance between their centers is 2.80 x 108 m. (b) What is the acceleration of the moon towards the planet

> A roller-coaster vehicle has a mass of 500 kg when fully loaded with passengers (Fig. P7.32). (a) If the vehicle has a speed of 20.0 m/s at point â’¶, what is the force of the track on the vehicle at this point? (b) What is the maximum sp

> A 40.0-kg child takes a ride on a Ferris wheel that rotates four times each minute and has a diameter of 18.0 m. (a) What is the centripetal acceleration of the child? (b) What force (magnitude and direction) does the seat exert on the child at the lowes

> Consider again the pairs of angular positions for the rigid object in Quick Quiz 7.1. If the object starts from rest at the initial angular position, moves counterclockwise with constant angular acceleration, and arrives at the final angular position wit

> Andrea and Chuck are riding on a merry-go-round. Andrea rides on a horse at the outer rim of the circular platform, twice as far from the center of the circular platform as Chuck, who rides on an inner horse. When the merry-go-round is rotating at a cons

> Why are new hires required to be reported to the state’s employment department?

> What is certified payroll? Which companies must use it?

> Why should more than one person prepare/verify payroll processing?

> What is the purpose of a payroll system?

> How does an FSA affect an employee’s taxable wages?

> What are the four categories of cafeteria plans?

> What are two types of insurance that may be deducted pre-tax under a cafeteria plan?

> Marty Burgess works for Hyrolated Sports. His compensation is based on sales of store products to customers. Which type of pay basis represents Marty’s pay?

> What are two examples of pre-tax deductions?

> What are two examples of voluntary deductions?

> Haley Price is an employee at Finesong Jewelry. She earns a salary of $38,850 per year, paid biweekly, and has a credit card garnishment. Assuming that Haley’s disposable income is 85 percent of her gross pay, what is the maximum amount per period that m

> What are two reports associated with fringe benefits?

> What are three examples of voluntary fringe benefits?

> Approximately what percentage of employee compensation includes fringe benefits?

> How often must employers deposit taxes associated with taxable fringe benefits?