A ball is thrown from the top of a cliff at an angle theta with respect to the horizontal direction with an initial speed of 10m/s. The kinetic energy of the ball when it strikes the ground willbe greatest when theta =
1. 0 degrees;because 0 degrees means a horizontal launch so no speed is wastedin the vertical direction.
2. 45 degrees; because 45 degrees gives the longest range for projectile motion and hence the greatest kinetic energy.
3. 90 degrees; because 90 degrees is a vertical launch so novelocity is wasted on horizontal motion.
4. all give the same kinetic energy; the overall vertical displacement is the same in all three cases so the change ingravitational energy is the same in all three cases.