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3 years ago

8

Xavier throws a tennis ball to his friend Olaf at a 20° angle relative to the ground with an initial velocity of 18 m/s. The ten

nis ball travels 30 m until Olaf catches itThe time the tennis ball was in the air, rounded to the nearest hundredth, is s.

1 answer:

Svetllana [295]3 years ago

3 0

Ball is thrown at an angle of 20 degree with velocity 18 m/s

so first we will find the two components of the velocity

$v_x = 18 cos20$

$v_x = 16.91 m/s$

similarly for other component

$v_y = 18 sin20$

$v_y = 6.16 m/s$

now the ball will cover horizontal distance of 30 m till it reach to other player

so here we can use the formula of time

$x = v_x * t$

$30 = 16.91 * t$

$t = \frac{30}{16.91}$

$t = 1.77 s$

so it will take 1.77 s to reach the other player

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