Two stones are thrown with the same initial speed at the same instant from the roof of a building. One stone is thrown at an angle of 30 degree above the horizontal; the other is thrown horizontally.(Neglect air resistance.), which of the following is true:(adsbygoogle = window.adsbygoogle || []).push({});

(a)The stones strike the ground at the same time and with equal speeds.

(b)The stones strike the ground at the same time with different speeds.

(c)The stones strike the ground at different times with equal speeds.

(d)The stones strike the ground at different times with different speed.

The answer is c. I understand why they arrive at different times. But I don't understand why they would arrive with equal speeds because the first stone was thrown 30 degrees higher than the second stone so wouldn't it have a higher U= mgh and thus a faster velocity?

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# Homework Help: Kinetic Energy and Potential Energy

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