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marshall27 [118]
3 years ago
6

While skateboarding at 19 km/h, Alana throws a tennis ball at 11 km/h to her friend Oliver. If Alana is the reference frame, the

speed of the tennis ball is
(Blank)
km/h.
Physics
2 answers:
nirvana33 [79]3 years ago
7 0
Haven't taken physics but I would assume if her friend is standing in front of her that you would add up the speeds and get 30 km/hr.
mariarad [96]3 years ago
4 0

Answer : Speed of tennis ball is 30 km/h.

Explanation :

Alana's speed on the skateboard is 19 km/h

She throws a tennis ball at 11 km/h

Alana is throwing a ball towards her friend Oliver.

That means the velocity of Alana and ball gets added up.

So, Speed of tennis ball is v_t=19\ km/h+11\ km/h=30\ km/h

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