A golf ball is given an initial speed of 20 m/s and returns to ground level. Which launch angle above level ground results in the ball traveling the greatest horizontal distance? Neglect friction.
1. 60 degrees
2. 45
3. 30
4. 15

The answer is 45 but I was wondering how to get there. The process.

  1. 👍 0
  2. 👎 0
  3. 👁 389
  1. If one ignores air resistance, then

    horizontal distance= V*cosTheta * t
    but t is dependent on time in the air.

    vertical distance= VsinTheta*t-1/2 g t^2=0

    or t= 2VsinTheta/g

    putting that into horizontal distance
    but cosThetasinTheta=1/2 sin(2theta)

    d=2V/g *sin(2theta)

    to find max distance, we take the first derivative and set to zero

    d/dtheta (2V/g*cos(2theta)*2)=0
    or 2theta=90 degrees, or theta=45 deg for max. For min distance, theta=0

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    A cricket ball is thrown at a speed of 30ms^-1 in a direction 30 degrees above the horizontal. Calculate: 1. The maximum height. 2. The time taken to return to the same level. 3. The distance from the thrower to where the ball

    asked by Tom Lisby on October 17, 2016
  2. physics - please help

    A golf ball of mass 0.045 kg is hit off the tee at a speed of 48 m/s. The golf club was in contact with the ball for 5.4 10-3 s. (a) Find the magnitude of the impulse imparted to the golf ball. (b) Find the magnitude of the

    asked by Anonymous on December 9, 2009
  3. Physics

    A soccer ball is kicked with an initial horizonal velocity of 18 m/s and an initial vertical velocity of 18 m/s. 1) What is the initial speed of the ball? 2)What is the initial angle of the ball with respect to the ground? 3)What

    asked by Aziz on September 29, 2011
  4. Algebra

    A golf ball is struck by a​ 60-degree golf club at an initial velocity of 84 feet per second. The height of the golf ball in feet is given by the quadratic function h(x)= 16 x^2/(42)^2+72.7/42x where x is the horizontal distance

    asked by Janice on June 25, 2015
  5. Algebra

    A golf ball is hit with an initial velocity of 140 ft per second at an inclination of 45 degrees to the horizontal. In​ physics, it is established that the height h of the golf ball is given by the function h(x)=-32x^2/140^2+x,

    asked by mu on October 7, 2015
  1. physics

    A golf ball is struck with a five iron on level ground. It lands 92.7 m away 4.40 s later. What was (a) the direction and (b) the magnitude of the initial velocity?

    asked by jessica on February 12, 2012
  2. Physics

    The place kicker on a football team kicks a ball from ground level with an initial speed of 8.30 m/s at an angle of 19.0° above the horizontal. How long is the ball in the air before it lands on the ground again? You may neglect

    asked by Emily on February 26, 2017
  3. Physics

    A tennis player hits a ball at ground level, giving it an initial velocity of 24 m/s at 57 degrees above the horizontal. (a) what are the horizontal and verticla components of the ball;s initial velocity? (b) how high above the

    asked by Sarah on June 7, 2009
  4. Physics

    A golfer tees off on level ground, giving the ball an initial speed of 46.5 m/s and an initial direction of 37.5 above the horizontal. a) how far from the golfer does the ball land? b) the next golfer in the group hits a ball with

    asked by Gabby on September 18, 2013
  5. Science

    A golf ball was hit and projected in an angle of 60 degrees with the horizontal. if the initial velocity of the ball was 50m/s, calculate the following: a. the time the golf ball was in the air b. horizontal distance the ball

    asked by YellowCorn on January 4, 2013
  6. Physics

    Alexis Farias realizes her dream to play golf on the moon. She hits a golf ball with an initial velocity of 23.5m/s at an angle of 35.0 degrees above the horizontal. The acceleration due to gravity on the moon is 1.67m/s^2. A).

    asked by Taylor on October 31, 2014

You can view more similar questions or ask a new question.