document.write( "Question 1170979: A ball is thrown off a 30 m cliff at 20 m/s at an angle of 60 degrees above the horizontal
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document.write( "What is the maximum height of the object?
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document.write( "What is the total hang time of the ball?
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document.write( "What is the final velocity of the ball?
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Algebra.Com's Answer #795857 by htmentor(1343) You can put this solution on YOUR website! The total height will be h0 + h, where h0 is the height of the cliff \n" ); document.write( "We can use the formula v2^2 = v1^2 + 2ah, with v1 = vy = 20*sin(60), and a = g \n" ); document.write( "h = vy^2/2g \n" ); document.write( "I assume total hang time refers to the time the ball takes to hit the ground. \n" ); document.write( "The time to reach maximum height is determined from v2 = v1 + at, \n" ); document.write( "with v2 = 0. Thus t = vy/g \n" ); document.write( "The time to fall from the maximum height to the ground is determined from \n" ); document.write( "h + h0 = v1t + 1/2at^2. Since v1 = 0, we have t = sqrt(2(h + h0)/g) \n" ); document.write( "Now for the final velocity, we need to determine the x and y components \n" ); document.write( "vx will remain constant throughout, and is equal to 20*cos(60) \n" ); document.write( "The y component of the final velocity is obtained from v2^2 = v1^2 + 2a(h+h0) \n" ); document.write( "with v1 = 0 \n" ); document.write( "I will leave it to you to fill in the values and get the final numbers \n" ); document.write( " \n" ); document.write( " |