New Semester
Started
Get
50% OFF
Study Help!
--h --m --s
Claim Now
Question Answers
Textbooks
Find textbooks, questions and answers
Oops, something went wrong!
Change your search query and then try again
S
Books
FREE
Study Help
Expert Questions
Accounting
General Management
Mathematics
Finance
Organizational Behaviour
Law
Physics
Operating System
Management Leadership
Sociology
Programming
Marketing
Database
Computer Network
Economics
Textbooks Solutions
Accounting
Managerial Accounting
Management Leadership
Cost Accounting
Statistics
Business Law
Corporate Finance
Finance
Economics
Auditing
Tutors
Online Tutors
Find a Tutor
Hire a Tutor
Become a Tutor
AI Tutor
AI Study Planner
NEW
Sell Books
Search
Search
Sign In
Register
study help
physics
physics scientists and engineers
Physics for Scientists and Engineers A Strategic Approach with Modern Physics 4th edition Randall D. Knight - Solutions
The earth’s radius is about 4000 miles. Kampala, the capital of Uganda, and Singapore are both nearly on the equator. The distance between them is 5000 miles. The flight from Kampala to Singapore takes 9.0 hours. What is the plane’s angular velocity with respect to the earth’s surface? Give
FIGURE EX4.25 shows the angular-velocity-versus-time graph for a particle moving in a circle, starting from θ0= 0 rad at t = 0 s. Draw the angular-position-versus-time graph. Include an appropriate scale on both axes.Figure Ex 4.25 w (rad/s) 20 10 - Fr(s) -10-
FIGURE EX4.24 shows the angular-position-versus-time graph for a particle moving in a circle. What is the particle€™s angular velocity at(a) t = 1 s,(b) t = 4 s, and(c) t = 7 s?Figure Ex 4.24 0 (гad) 4т 2т -г (8) -2т.
FIGURE EX4.23 shows the angular-velocity-versus-time graph for a particle moving in a circle. How many revolutions does the object make during the first 4 s?Figure Ex 4.23 w (rad/s) 20- 10- t (s) 0- 3.
Susan, driving north at 60 mph, and Trent, driving east at 45 mph, are approaching an intersection. What is Trent’s speed relative to Susan’s reference frame?
A kayaker needs to paddle north across a 100-m-wide harbor. The tide is going out, creating a tidal current that flows to the east at 2.0 m/s. The kayaker can paddle with a speed of 3.0 m/s.a. In which direction should he paddle in order to travel straight across the harbor?b. How long will it take
Mary needs to row her boat across a 100-m-wide river that is flowing to the east at a speed of 1.0 m/s. Mary can row with a speed of 2.0 m/s.a. If Mary points her boat due north, how far from her intended landing spot will she be when she reaches the opposite shore?b. What is her speed with respect
When the moving sidewalk at the airport is broken, as it often seems to be, it takes you 50 s to walk from your gate to baggage claim. When it is working and you stand on the moving sidewalk the entire way, without walking, it takes 75 s to travel the same distance. How long will it take you to
A boat takes 3.0 hours to travel 30 km down a river, then 5.0 hours to return. How fast is the river flowing?
A baseball player friend of yours wants to determine his pitching speed. You have him stand on a ledge and throw the ball horizontally from an elevation 4.0 m above the ground. The ball lands 25 m away. What is his pitching speed?
A ball thrown horizontally at 25 m/s travels a horizontal distance of 50 m before hitting the ground. From what height was the ball thrown?
You have a remote-controlled car that has been programmed to have velocitywhere t is in s. At t = 0 s, the car is atWhat are the car€™s(a) Position vector and(b) Acceleration vector at t = 2.0 s? 3= (-3tî + 2t²f) m/s, To = (3.0î + 2.0) m.
A supply plane needs to drop a package of food to scientists working on a glacier in Greenland. The plane flies 100 m above the glacier at a speed of 150 m/s. How far short of the target should it drop the package?
On the Apollo 14 mission to the moon, astronaut Alan Shepard hit a golf ball with a 6 iron. The free-fall acceleration on the moon is 1/6 of its value on earth. Suppose he hit the ball with a speed of 25 m/s at an angle 30° above the horizontal.a. How much farther did the ball travel on the moon
In the Olympic shot-put event, an athlete throws the shot with an initial speed of 12.0 m/s at a 40.0° angle from the horizontal. The shot leaves her hand at a height of 1.80 m above the ground. How far does the shot travel?
A rifle is aimed horizontally at a target 50 m away. The bullet hits the target 2.0 cm below the aim point.a. What was the bullet’s flight time?b. What was the bullet’s speed as it left the barrel?
Sand moves without slipping at 6.0 m/s down a conveyer that is tilted at 15°. The sand enters a pipe 3.0 m below the end of the conveyer belt, as shown in FIGURE P4.56. What is the horizontal distance d between the conveyer belt and the pipe?Figure P4.56 6.0 m/s 15 3.0 m
You are watching an archery tournament when you start wondering how fast an arrow is shot from the bow. Remembering your physics, you ask one of the archers to shoot an arrow parallel to the ground. You find the arrow stuck in the ground 60 m away, making a 3.0° angle with the ground. How fast was
FIGURE Q4.13 shows three points on a steadily rotating wheel.a. Rank in order, from largest to smallest, the angular velocities ω1, ω2, and ω3 of these points. Explain.b. Rank in order, from largest to smallest, the speeds v1, v2, and v3 of these points.
In uniform circular motion, which of the following quantities are constant: speed, instantaneous velocity, the tangential component of velocity, the radial component of acceleration, the tangential component of acceleration? Which of these quantities are zero throughout the motion?
In FIGURE Q4.11, Yvette and Zack are driving down the freeway side by side with their windows down. Zack wants to toss his physics book out the window and have it land in Yvette€™s front seat. Ignoring air resistance, should he direct his throw outward and toward the front of the car
Zack is driving past his house in FIGURE Q4.10. He wants to toss his physics book out the window and have it land in his driveway. If he lets go of the book exactly as he passes the end of the driveway, should he direct his throw outward and toward the front of the car (throw 1), straight outward
Anita is running to the right at 5 m/s in FIGURE Q4.8. Balls 1 and 2 are thrown toward her by friends standing on the ground. According to Anita, both balls are approaching her at 10 m/s.Which ball was thrown at a faster speed? Or were they thrown with the same speed? Explain.Figure Q4.8 5 m/s
A cart that is rolling at constant velocity on a level table fires a ball straight up.a. When the ball comes back down, will it land in front of the launching tube, behind the launching tube, or directly in the tube? Explain.b. Will your answer change if the cart is accelerating in the forward
For a projectile, which of the following quantities are constant during the flight: x, y, r, vx, vy, v, ax, ay? Which of these quantities are zero throughout the flight?
A flock of ducks is trying to migrate south for the winter, but they keep being blown off course by a wind blowing from the west at 6.0 m/s. A wise elder duck finally realizes that the solution is to fly at an angle to the wind. If the ducks can fly at 8.0 m/s relative to the air, what direction
Tom is climbing a 3.0-m-long ladder that leans against a vertical wall, contacting the wall 2.5 m above the ground. His weight of 680 N is a vector pointing vertically downward. (Weight is measured in newtons, abbreviated N.) What are the components of Tom’s weight parallel and perpendicular to
Your neighbor Paul has rented a truck with a loading ramp. The ramp is tilted upward at 25°, and Paul is pulling a large crate up the ramp with a rope that angles 10° above the ramp. If Paul pulls with a force of 550 N, what are the horizontal and vertical components of his force?
Dee is on a swing in the playground. The chains are 2.5 m long, and the tension in each chain is 450 N when Dee is 55 cm above the lowest point of her swing. Tension is a vector directed along the chain, measured in newtons, abbreviated N. What are the horizontal and vertical components of the
Kami is walking through the airport with her two-wheeled suitcase. The suitcase handle is tilted 40° from vertical, and Kami pulls parallel to the handle with a force of 120 N. (Force is measured in newtons, abbreviated N.) What are the horizontal and vertical components of her applied force?
A pine cone falls straight down from a pine tree growing on a 20° slope. The pine cone hits the ground with a speed of 10 m/s. What is the component of the pine cone’s impact velocity(a) Parallel to the ground and(b) Perpendicular to the ground?
Jack and Jill ran up the hill at 3.0 m/s. The horizontal component of Jill’s velocity vector was 2.5 m/s.a. What was the angle of the hill?b. What was the vertical component of Jill’s velocity?
You are fixing the roof of your house when a hammer breaks loose and slides down. The roof makes an angle of 35° with the horizontal, and the hammer is moving at 4.5 m/s when it reaches the edge. What are the horizontal and vertical components of the hammer’s velocity just as it leaves the roof?
A cannon tilted upward at 30° fires a cannonball with a speed of 100 m/s. What is the component of the cannonball’s velocity parallel to the ground?
You go to an amusement park with your friend Betty, who wants to ride the 30-m-diameter Ferris wheel. She starts the ride at the lowest point of a wheel that, as you face it, rotates counterclockwise. What is her displacement vector when the wheel has rotated by an angle of 60°? Give your answer
The minute hand on a watch is 2.0 cm in length. What is the displacement vector of the tip of the minute handa. From 8:00 to 8:20 A.M.?b. From 8:00 to 9:00 A.M.?
A runner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. Let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. The runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times
Are the following statements true or false? Explain your answer.(a) The magnitude of a vector can be different in different coordinate systems.(b) The direction of a vector can be different in different coordinate systems.(c) The components of a vector can be different in different coordinate
Suppose two vectors have unequal magnitudes. Can their sum be zero? Explain.
Can a vector have zero magnitude if one of its components is nonzero? Explain.
Can a vector have a component equal to zero and still have nonzero magnitude? Explain.
Is it possible to add a scalar to a vector? If so, demonstrate. If not, explain why not.
Can the magnitude of the displacement vector be more than the distance traveled? Less than the distance traveled? Explain.
The Starship Enterprise returns from warp drive to ordinary space with a forward speed of 50 km/s. To the crew’s great surprise, a Klingon ship is 100 km directly ahead, traveling in the same direction at a mere 20 km/s. Without evasive action, the Enterprise will overtake and collide with the
A rubber ball is shot straight up from the ground with speed v0. Simultaneously, a second rubber ball at height h directly above the first ball is dropped from rest.a. At what height above the ground do the balls collide? Your answer will be an algebraic expression in terms of h, v0, and g.b. What
A sprinter can accelerate with constant acceleration for 4.0 s before reaching top speed. He can run the 100 meter dash in 10.0 s. What is his speed as he crosses the finish line?
Careful measurements have been made of Olympic sprinters in the 100 meter dash. A quite realistic model is that the sprinter’s velocity is given byvx = a(1 - e-bt)Where t is in s, vx is in m/s, and the constants a and b are characteristic of the sprinter. Sprinter Carl Lewis’s run at the
Careful measurements have been made of Olympic sprinters in the 100 meter dash. A simple but reasonably accurate model is that a sprinter accelerates at 3.6 m/s2 for 3 1/3 s, then runs at constant velocity to the finish line.a. What is the race time for a sprinter who follows this model?b. A
A rocket is launched straight up with constant acceleration. Four seconds after liftoff, a bolt falls off the side of the rocket. The bolt hits the ground 6.0 s later. What was the rocket’s acceleration?
You are given the kinematic equation or equations that are used to solve a problem. For each of these, you are to:a. Write a realistic problem for which this is the correct equation(s). Be sure that the answer your problem requests is consistent with the equation(s) given.b. Draw the pictorial
The two masses in FIGURE P2.75 slide on friction less wires. They are connected by a pivoting rigid rod of length L. Prove that v2x= - v1ytan θ.Figure P2.75 L.
When a 1984 Alfa Romeo Spider sports car accelerates at the maximum possible rate, its motion during the first 20 s is extremely well modeled by the simple equationWhere P = 3.6 × 104 watts is the car€™s power output, m = 1200 kg is its mass, and vx is in m/s. That is, the
Your goal in laboratory is to launch a ball of mass m straight up so that it reaches exactly height h above the top of the launching tube. You and your lab partners will earn fewer points if the ball goes too high or too low. The launch tube uses compressed air to accelerate the ball over a
As an astronaut visiting Planet X, you’re assigned to measure the free-fall acceleration. Getting out your meter stick and stop watch, you time the fall of a heavy ball from several heights. Your data are as follows:Height (m) _____________ Fall time (s)0.0 …………………………. 0.001.0
A motorist is driving at 20 m/s when she sees that a traffic light 200 m ahead has just turned red. She knows that this light stays red for 15 s, and she wants to reach the light just as it turns green again. It takes her 1.0 s to step on the brakes and begin slowing. What is her speed as she
One game at the amusement park has you push a puck up a long, friction less ramp. You win a stuffed animal if the puck, at its highest point, comes to within 10 cm of the end of the ramp without going off. You give the puck a push, releasing it with a speed of 5.0 m/s when it is 8.5 m from the end
Bob is driving the getaway car after the big bank robbery. He’s going 50 m/s when his headlights suddenly reveal a nail strip that the cops have placed across the road 150 m in front of him. If Bob can stop in time, he can throw the car into reverse and escape. But if he crosses the nail strip,
A very slippery block of ice slides down a smooth ramp tilted at angle θ. The ice is released from rest at vertical height h above the bottom of the ramp. Find an expression for the speed of the ice at the bottom?
Amir starts riding his bike up a 200-m-long slope at a speed of 18 km/h, decelerating at 0.20 m/s2 as he goes up. At the same instant, Becky starts down from the top at a speed of 6.0 km/h, accelerating at 0.40 m/s2 as she goes down. How far has Amir ridden when they pass?
Ann and Carol are driving their cars along the same straight road. Carol is located at x = 2.4 mi at t = 0 h and drives at a steady 36 mph. Ann, who is traveling in the same direction, is located at x = 0.0 mi at t = 0.50 h and drives at a steady 50 mph.a. At what time does Ann overtake Carol?b.
You are 9.0 m from the door of your bus, behind the bus, when it pulls away with an acceleration of 1.0 m/s2. You instantly start running toward the still-open door at 4.5 m/s.a. How long does it take for you to reach the open door and jump in?b. What is the maximum time you can wait before
A basketball player can jump to a height of 55 cm. How far above the floor can he jump in an elevator that is descending at a constant 1.0 m/s?
A hotel elevator ascends 200 m with a maximum speed of 5.0 m/s. Its acceleration and deceleration both have a magnitude of 1.0 m/s2.a. How far does the elevator move while accelerating to full speed from rest?b. How long does it take to make the complete trip from bottom to top?
A lead ball is dropped into a lake from a diving board 5.0 m above the water. After entering the water, it sinks to the bottom with a constant velocity equal to the velocity with which it hit the water. The ball reaches the bottom 3.0 s after it is released. How deep is the lake?
A 1000 kg weather rocket is launched straight up. The rocket motor provides a constant acceleration for 16 s, then the motor stops. The rocket altitude 20 s after launch is 5100 m. You can ignore any effects of air resistance. What was the rocket’s acceleration during the first 16 s?
A 200 kg weather rocket is loaded with 100 kg of fuel and fired straight up. It accelerates upward at 30 m/s2 for 30 s, then runs out of fuel. Ignore any air resistance effects.a. What is the rocket’s maximum altitude?b. How long is the rocket in the air before hitting the ground?
You are at a train station, standing next to the train at the front of the first car. The train starts moving with constant acceleration, and 5.0 s later the back of the first car passes you. How long does it take after the train starts moving until the back of the seventh car passes you? All cars
A cheetah spots a Thomson’s gazelle, its preferred prey, and leaps into action, quickly accelerating to its top speed of 30 m/s, the highest of any land animal. However, a cheetah can maintain this extreme speed for only 15 s before having to let up. The cheetah is 170 m from the gazelle as it
You are playing miniature golf at the golf course shown in FIGURE P2.51. Due to the fake plastic grass, the ball decelerates at 1.0 m/s2when rolling horizontally and at 6.0 m/s2on the slope. What is the slowest speed with which the ball can leave your golf club if you wish to make a hole in
Two cars are driving at the same constant speed on a straight road, with car 1 in front of car 2. Car 1 suddenly starts to brake with constant acceleration and stops in 10 m. At the instant car 1 comes to a stop, car 2 begins to brake with the same acceleration. It comes to a halt just as it
You’re driving down the highway late one night at 20 m/s when a deer steps onto the road 35 m in front of you. Your reaction time before stepping on the brakes is 0.50 s, and the maximum deceleration of your car is 10 m/s2.a. How much distance is between you and the deer when you come to a
You are driving to the grocery store at 20 m/s. You are 110 m from an intersection when the traffic light turns red. Assume that your reaction time is 0.50 s and that your car brakes with constant acceleration. What magnitude braking acceleration will bring you to a stop exactly at the intersection?
FIGURE P2.46 shows a set of kinematic graphs for a ball rolling on a track. All segments of the track are straight lines, but some may be tilted. Draw a picture of the track and also indicate the ball€™s initial condition.Figure P2.46
The takeoff speed for an Airbus A320 jetliner is 80 m/s. Velocity data measured during takeoff are as shown.t (s) ___________ vx (m/s)0 …………………….. 010 ………………….. 2320 ………………….. 4630 ………………….. 69a. Is the jetliner’s acceleration constant
Draw position, velocity, and acceleration graphs for the ball shown in FIGURE P2.44. See Problem 43 for more information.Figure P2.44 Vor
FIGURE P2.45 shows a set of kinematic graphs for a ball rolling on a track. All segments of the track are straight lines, but some may be tilted. Draw a picture of the track and also indicate the ball€™s initial condition.Figure P2.45
A ball rolls along the smooth track shown in FIGURE P2.43. Each segment of the track is straight, and the ball passes smoothly from one segment to the next without changing speed or leaving the track. Draw three vertically stacked graphs showing position, velocity, and acceleration versus time.
A particle’s velocity is given by the function vx = (2.0 m/s) sin (pt), where t is in s.a. What is the first time after t = 0 s when the particle reaches a turning point?b. What is the particle’s acceleration at that time?
A particle’s acceleration is described by the function ax = (10 – t) m/s2, where t is in s. Its initial conditions are x0 = 0 m and v0x = 0 m/s at t = 0 s.a. At what time is the velocity again zero?b. What is the particle’s position at that time?
A particle’s velocity is described by the function vx = k t2 m/s, where k is a constant and t is in s. The particle’s position at t0 = 0 s is x0 = - 9.0 m. At t1 = 3.0 s, the particle is at x1 = 9.0 m. Determine the value of the constant k. Be sure to include the proper units?
A particle’s velocity is described by the function vx = (t2 - 7t + 10) m/s, where t is in s.a. At what times does the particle reach its turning points?b. What is the particle’s acceleration at each of the turning points?
A block is suspended from a spring, pulled down, and released. The block€™s position-versus-time graph is shown in FIGURE P2.38.a. At what times is the velocity zero? At what times is the velocity most positive? Most negative?b. Draw a reasonable velocity-versus-time graph.Figure P2-38
Particles A, B, and C move along the x-axis. Particle C has an initial velocity of 10 m/s. In FIGURE P2.37, the graph for A is a position-versus-time graph; the graph for B is a velocity-versus time graph; the graph for C is an acceleration-versus-time graph. Find each particle€™s
The position of a particle is given by the function x = (2t3 – 6t2 + 12) m, where t is in s.a. At what time does the particle reach its minimum velocity? What is (vx)min?b. At what time is the acceleration zero?
The position of a particle is given by the function x = (2t3 - 9t2 + 12) m, where t is in s.a. At what time or times is vx = 0 m/s?b. What are the particle’s position and its acceleration at this time(s)?
A particle moving along the x-axis has its velocity described by the function vx = 2t2 m/s, where t is in s. Its initial position is x0 = 1 m at t0 = 0 s. At t = 1 s what are the particle’s(a) Position,(b) Velocity, and(c) Acceleration?
A particle moving along the x-axis has its position described by the function x = (2t3 + 2t + 1) m, where t is in s. At t = 2 s what are the particle’s(a) Position,(b) Velocity, and(c) Acceleration?
FIGURE EX2.32 shows the acceleration graph for a particle that starts from rest at t = 0 s. What is the particle€™s velocity at t = 6 s?Figure Ex 2.32 a, (m/s?) 10- 5- 0- -t (s) 2
FIGURE EX2.31 shows the acceleration-versus-time graph of a particle moving along the x-axis. Its initial velocity is v0x= 8.0 m/s at t0= 0 s. What is the particle€™s velocity at t = 4.0 s?Figure Ex 2.31 az (m/s*) 4- 2- t (s)
A small child gives a plastic frog a big push at the bottom of a slippery 2.0-m-long, 1.0-m-high ramp, starting it with a speed of 5.0 m/s. What is the frog’s speed as it flies off the top of the ramp?
A snowboarder glides down a 50-m-long, 15o hill. She then glides horizontally for 10 m before reaching a 25o upward slope.Assume the snow is friction less.a. What is her velocity at the bottom of the hill?b. How far can she travel up the 25o slope?
A skier is gliding along at 3.0 m/s on horizontal, friction less snow. He suddenly starts down a 10o incline. His speed at the bottom is 15 m/s.What is the length of the incline?How long does it take him to reach the bottom?
A rock is dropped from the top of a tall building. The rock’s displacement in the last second before it hits the ground is 45% of the entire distance it falls. How tall is the building?
As a science project, you drop a watermelon off the top of the Empire State Building, 320 m above the sidewalk. It so happens that Superman flies by at the instant you release the watermelon. Superman is headed straight down with a speed of 35 m/s. How fast is the watermelon going when it passes
A rock is tossed straight up from ground level with a speed of 20 m/s. When it returns, it falls into a hole 10 m deep.(a) What is the rock’s velocity as it hits the bottom of the hole?(b) How long is the rock in the air, from the instant it is released until it hits the bottom of the hole?
A student standing on the ground throws a ball straight up. The ball leaves the student’s hand with a speed of 15 m/s when the hand is 2.0 m above the ground. How long is the ball in the air before it hits the ground? (The student moves her hand out of the way.)
A car starts from rest at a stop sign. It accelerates at 4.0 m/s2 for 6.0 s, coasts for 2.0 s, and then slows down at a rate of 3.0 m/s2 for the next stop sign. How far apart are the stop signs?
A Porsche challenges a Honda to a 400 m race. Because the Porsche’s acceleration of 3.5 m/s2 is larger than the Honda’s 3.0 m/s2, the Honda gets a 1.0 s head start. Who wins? By how many seconds?
A speed skater moving to the left across friction less ice at 8.0 m/s hits a 5.0-m-wide patch of rough ice. She slows steadily, then continues on at 6.0 m/s. What is her acceleration on the rough ice?
When you sneeze, the air in your lungs accelerates from rest to 150 km/h in approximately 0.50 s. What is the acceleration of the air in m/s2?
Showing 3500 - 3600
of 3693
First
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
Step by Step Answers
Get 50% OFF
Claim Now
