1. J

    Finding speed with basically just distance.

    Hi, I'm currently in the process of trying to learn how to use quadratics to find out speed/distance/time etc. My program that I'm taking is often very unclear and skims over topics regularly. The example I was given to learn the process was fairly straightforward and easy to learn, however the...
  2. A

    Very vague question about speed, distance, time

    It goes like this: "Ed goes 20mph in one direction, and 50 mph on the return trip. His average speed is?" I am just not getting the explanation in the book, if anybody could explain how this is done, I would be extremely grateful, thanks
  3. W

    terminal velocity (M1)

    A skydiver of mass m kg steps out of an aircraft and starts to fall. The air resistance when his speed is v ms^-1 is given by kv^2 newtons. If his terminal speed is 40 ms^-1, find an expression for k in terms of m. (I did this part, got (m/160), which is correct) When his speed reaches 16 ms^-1...
  4. J

    Approximating maximum speed of a particle in terms of angular speed

    Here is a rule that governs the motion of particles in my hypothetical Cartesian plane universe: - a particle can move a maximum distance of Vx units along the x-axis and Vy units along the y-axis per one unit of time. - the acceleration along the axes is also bounded. The limits are Ax for the...
  5. J

    Speed of Shadow

    A train is moving at 60 mi/h on a straight track in the direction N 37° W. The sun, setting in the direction N 80° W, casts the train's shadow onto the front of a building that faces due west. How fast is the train's shadow moving?
  6. M

    Angular speed, linear speed, and linear speed at halfway point.

    rpm = 500 ; r=45cm (A) Angular Speed: to find the angular speed in units of radian/seconds I know the radian measure of a circle which is 2pirad... then 500 rev/60 secs x 2pirad/1rev I get the answer 52.35 cm but they are getting the answer 50pi/3?? I have no idea how they are...
  7. J

    Travelling along which one of these paths will allow me to maintain target speed?

    Hello All, I only have a vary basic understanding of physical concepts so please bear with me. Suppose I want to travel from point A to point B and maintain speed (magnitude of velocity) as close as possible to some target constant speed C for as much of the way as I can; I cannot stray from...
  8. Z

    Collision Result

    No idea if this even belongs in Calculus, math was never my strong suit, so apologies if posting in the wrong section. I need help with what equation to use to figure this out. I've done a lot of google searches and think it has to do with Ft = ma or m1 x v1 = m2 x v2, but I'm not quite sure...
  9. A

    Data Forecasting (Wind Speed)

    Hi, I am engineer, therefore, know very little about the typical terminologies of stat and forecasting. Anyway, I tried to explain my prob. in simple word. I want to generate/forecast wind speed values. The data, I have are: I) Mean II) Max. and Min. differences from mean for the whole period...
  10. J

    Speed in a Clockwise Circle

    A particle starting from rest revolves with uniformly increasing speed in a clockwise circle in the xy plane. The center of the circle is at the origin of an xy coordinate system. At t = 0, the particle is at x = 0, y = 2 m. At t = 2 s, it has made one-quarter of a revolution and is at x = 2 m...
  11. B

    Find Scalar Tangential/Normal Component of Acceleration Given Speed

    Hello! I have two different questions, one asking for the scalar tangential component of acceleration and the other asking for the scalar normal component of acceleration, both given the speed, ||v||. I could really use some help with how to start solving these specific types of problems as my...
  12. Jason76


    - Hint on beginning setup?
  13. Jason76

    Speed at Impact - # 2

    A projectile is fired with an initial speed of 170 m/s and angle of elevation of 60 degrees. Find speed at impact. t = 42.4175707974285 y(t) = v_{0}\sin\theta - 4.9t^{2} y(t) = 170\sin(60)t - 4.9t^{2} + 100 y'(t) = 170\sin(60) - 9.8t y'(t) = 85\sqrt{3} - 9.8t x(t)...
  14. Jason76

    Speed at Impact

    A projectile is fired with an initial speed of 240 m/s and angle of elevation of 60 degrees, and it's fired 100 m off the ground. Find speed at impact. y(t) = v_{0}\sin\theta - 4.9t^{2} y(t) = 240\sin(60)t - 4.9t^{2} + 100 y'(t) = 240\sin(60) - 9.8t y'(t) = 207.8460969 -...
  15. J

    Linear Speed - Torque

    Suppose the force Ft in the cord hanging from the wheel is given by the relation Ft = 3t - 0.2t^2 (newtons) where t is in seconds. If the wheel starts from rest, what is the linear speed of a point on its rim 8 s later? The Ft force is perpendicular to the wheel's (4 kg) radius = 33 cm. The...
  16. C

    Physic problem about speed

    A certain airport runway of length L allows planes to accelerate uniformly from rest to takeoff speed using the full length of the runway. Because of newly designed planes, the takeoff speed must be doubled, again using the full length of the runway and having the same acceleration as before. In...
  17. R

    Angular and Linear Speed

    I seek a detailed explanation in terms of how this is done. I am not too clear in terms of angular and linear speed questions. Let us say that a belt drives two wheels of radii r and R, as shown in the picture. If r = 6 cm, R = 10 cm and the angular speed of the larger wheel is 100 rpm...
  18. R

    Angular and Linear Speed

    In its most basic definition, what exactly is angular and linear speed? What formulas represent angular and linear speed? How are the formulas used to solve questions? What connection is there between angular speed, linear speed and radian measure?
  19. S

    Speed equals distance divided by time

    How do I turn the fraction: Distance Speed =_______ Time into something I can use to calculate the time? I thought it would be: Distance Time =________ Speed
  20. Z

    Speed Time and Distance

    hello all... i have a question : "John riding a bike from city A to city B. He departed at 07.00 am with speed of 60 kmph . From town A , Sisca followed with a speed of 80 kmph , what time Sisca followed John ? the answer : a) 10.00 am b) 11.00 am c) 12.00 am d) 13.00 am how to solve this...