Question

Please help! Thank you!

The best leaper in the animal kingdom is the puma, which can jump to a height of 3.7 m when leaving the ground at an angle of 45 degree. With what speed must the animal leave the ground to reach that height? A place-kicker must kick a football from a point 36.0 m (about 40 yards) from the goal. Half the crowd hopes the ball will clear the crossbar, which is 3.05 m high. When kicked, the ball leaves the ground with a speed of 22.6 m/s at an angle of 52.0 degree to the horizontal. By how much does the ball clear or fall short (vertically) of clearing the crossbar? (Enter a negative answer if it falls short.) m Does the ball approach the crossbar (and cross above or beneath it) while still rising or while falling? rising falling

Answer 1

max height on projectile h = 3. 7m theta = 45 degree h = v_0^2 sin^2 theta/2g 3. 7 = v_0^2 times 1/2 times 9. 8 x^2 Speed Required, V_0 = 12. 04 m/s ii) Required height h = 3. 05m, x = 36. m v_0 = 22. 6 m/s theta = 52 degre h = v_0t sin theta - 1/2 gt^2 x = v_0t cos theta 36 = 22. 6t cos 52 degree time to reach 36m horizontally t = 2. 587 sec actual height, h� = 22. 6 times 2. 587 - 1/2 times 9. 8 times (2. 587) ^2 h� = 13. 28 m Ball clears by h� - n = 10. 23 m time to reach max height t_m = v_0 sin theta/g = 22. 6 times sin52/9. 8 = 1. 81 sec at 36 m time is 2. 587 sec So Ball is falling