1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Please help me with my up coming exams

  1. Jan 20, 2008 #1
    hello to all the great people in this site...I came across these questions and I have an exam early Tuesday morning and I would like you guys to help me with it, please I need to make an A in the class and these questions I don't know where to start from..please I beg you guys to help I REALLY NEED YOUR HELP ALL OF YOU IF YOU CAN HELP ME

    A mountain-climbing expedition establishes two intermediate camps, labeled A and B in the drawing, above the base camp. What is the magnitude r of the displacement between camp A and camp B?



    A skateboarder, starting from rest, rolls down a 11.6-m ramp. When she arrives at the bottom of the ramp her speed is 7.71 m/s. (a) Determine the magnitude of her acceleration, assumed to be constant. (b) If the ramp is inclined at 29.7 ° with respect to the ground, what is the component of her acceleration that is parallel to the ground?



    #3)A car drives horizontally off the edge of a cliff that is 50.0 m high. The police at the scene of the accident note that the point of impact is 162 m from the base of the cliff. How fast was the car traveling when it drove off the cliff?


    #4)A quarterback claims that he can throw the football a horizontal distance of 195 m. Furthermore, he claims that he can do this by launching the ball at the relatively low angle of 34.6 ° above the horizontal. To evaluate this claim, determine the speed with which this quarterback must throw the ball. Assume that the ball is launched and caught at the same vertical level and that air resistance can be ignored. For comparison a baseball pitcher who can accurately throw a fastball at 45 m/s (100 mph) would be considered exceptional.

    #5)The lob in tennis is an effective tactic when your opponent is near the net. It consists of lofting the ball over his head, forcing him to move quickly away from the net (see the drawing). Suppose that you loft the ball with an initial speed of 15.0 m/s at an angle of 50.0° the horizontal. At this instant your opponent is 10.0 m away from the ball. He begins moving away from you 0.35 s later, hoping to reach the ball and hit it back at the moment that it is 2.10 m above its launch point. With what minimum average speed must he move? (Ignore the fact that he can stretch, so that his racket can reach the ball before he does.

    #6) A baseball is hit into the air at an initial speed of 31.0 m/s and an angle of 41.8 ° above the horizontal. At the same time, the center fielder starts running away from the batter and catches the ball 0.829 m above the level at which it was hit. If the center fielder is initially 1.07 x 102 m from home plate, what must be his average speed?


    #7)Two cars, A and B, are traveling in the same direction, although car A is 102 m behind car B. The speed of A is 26.0 m/s, and the speed of B is 18.7 m/s. How much time does it take for A to catch B?


    #8)A speed ramp at an airport is a moving conveyor belt on which you can either stand or walk. It is intended to get you from place to place more quickly. Suppose a speed ramp is 123 m long. When you walk at a comfortable speed on the ground, you cover this distance in 82.1 s. When you walk on the speed ramp at this same comfortable speed, you cover this distance in 30.0 s. Determine the speed at which the speed ramp is moving relative to the ground.


    #9)On a pleasure cruise a boat is traveling relative to the water at a speed of 5.93 m/s due south. Relative to the boat, a passenger walks toward the back of the boat at a speed of 1.65 m/s. (a) What is the magnitude of the passenger's velocity relative to the water? (b) How long does it take for the passenger to walk a distance of 30.1 m on the boat? (c) How long does it take for the passenger to cover a distance of 30.1 m on the water?


    #10)A jetliner can fly 6.73 hours on a full load of fuel. Without any wind it flies at a speed of 3.16 x 102 m/s. The plane is to make a round-trip by heading due west for a certain distance, turning around, and then heading due east for the return trip. During the entire flight, however, the plane encounters a 68.0-m/s wind from the jet stream, which blows from west to east. What is the maximum distance (in kilometers) that the plane can travel due west and just be able to return home?

  2. jcsd
  3. Jan 20, 2008 #2
    hey bro...it shall be much more helpful for ya if ya categorised yr questions and posted them as independent threads....

    indicate the chapter name in the heading and split ur ques in various posts...

    accumulating the ques limits the views...
  4. Jan 20, 2008 #3
    seriously... what you're expecting is that we solve the questions for you. This is not gonna happen.. and if anyone tries to do it completely for you.. he'll most probably get a warning from the pf staff [as i have..]. you have to show some work you have done before we assist you.

    And from your thread, you have posted nothing that you've done yourself.
  5. Jan 20, 2008 #4


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    Dearly Missed

    Please give us a few hints, your questions are way too difficult to solve without you helping us along a bit.
  6. Jan 20, 2008 #5
    And this will help you with your upcoming exams how?
  7. Jan 20, 2008 #6
    you are saying this.. i mean.. you've got 8000+ posts here.. it sorta confuses me...
  8. Jan 20, 2008 #7
    he was being sarcastic
  9. Jan 20, 2008 #8
    i am so sorry.. i thought he was saying that to me and the poster b4 me.. gosh.. this is so stupid of me here.. damn..
  10. Jan 21, 2008 #9
    What The Hell Is Wrong With All Of You
    Its Not Like The End Of The World If I Asked You Quiestions
    It Doesnt Mean Helping Me Its Gonna Be The End Of The World
    Plz Get A Life All Of You
  11. Jan 21, 2008 #10
    rohanprabhu I NEVER said that I wanted you to do my work
    and thanks in advance
  12. Jan 21, 2008 #11


    User Avatar
    Homework Helper

    Nice attitude. Talk about rude! :rolleyes: You aren't going to get much help if you continue to insult people.

    If you seriously want help, then show us your attempts at solving these problems. I refuse to believe you can't even start one of these questions. Do you not have a textbook?
  13. Jan 21, 2008 #12
    i know you NEVER said.. but you very well implied it.

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook