A ball is launched at an angle of 39.8 degrees up from the horizontal, with a muzzle velocity of 6.6 meters per second, from a launch point which is 1 meters above the floor. How high will the ball be above the floor (in meters), when it is a horizontal distance of 2.7 meters away? Use 9.82 meters per second for "g".

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Answer:

1.85 m

Explanation:

The horizontal velocity of the ball is

[tex]v_x = v cos \theta = (6.6 m/s) cos 39.8^{\circ}=5.1 m/s[/tex]

The horizontal distance travelled is

d = 2.7 m

And since the motion along the horizontal direction is a uniform motion, the time taken is

[tex]t= \frac{d}{v_x}=\frac{2.7 m}{5.1 m/s}=0.53 s[/tex]

The vertical position of the ball is given by

[tex]y= h + u_y t - \frac{1}{2}gt^2[/tex]

where

h = 1 m is the initial heigth

[tex]u_y = v sin \theta = (6.6 m/s) sin 39.8^{\circ}=4.2 m/s[/tex] is the initial vertical velocity

g = 9.82 m/s^2 is the acceleration due to gravity

Substituting t = 0.53 s, we find the height of the ball at this time:

[tex]y=1 m + (4.2 m/s)(0.53 s) - \frac{1}{2}(9.82 m/s^2)(0.53 s)^2=1.85 m[/tex]

Answer:

To convert kilometers per hour to meters per second, perform dimensional analysis. Remember that:

1 km = 1000 m

1 hr = 3600 seconds

Using these conversion, perform dimensional analysis:  

16.2 km/ hr (1000m/1km) (1hr/60 sec) = 4.5 m/s

The analysis basically just uses the conversion factors and canceling of units. The final answer is 4.5 m/s.  

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Correction: That should be *(1 hr/3600 sec). The answer is still 4.5 m/s.

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Hope this helps, i did the test and this answer was right, oh and brainliest, Good luck.