How Do You Calculate Time and Speed in These Physics Problems?

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To calculate time and speed in physics problems, understanding the equations of motion is crucial. For the first problem, the time a balloon is in the air can be found using the equation for free fall, considering gravitational acceleration. The second problem requires determining the initial speed of the second arrow, factoring in the time delay and the heights reached. The third problem involves analyzing the motion of two balls, one dropped and one thrown, to find where they intersect. Lastly, the fourth question simply requires calculating the distance traveled by both the sloth and tortoise to find the difference after 20 minutes.
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Physics questions...

1.) From her bedroom window a girl drops a water-filled balloon to the ground, 5.53 m below. If the balloon is released from rest, how long is it in the air? ** they didn't give me any velocity, so i don't know waht to do **

2.) Two arrows are shot vertically upward. The second arrow is shot after the first one, but while the first is still on its way up. The initial speeds are such that both arrows reach their maximum heights at the same instant, although these heights are different. Suppose that the initial speed of the first arrow is 25.6 m/s and that the second arrow is fired 2 s after the first. Determine the initial speed of the second arrow. ** ím lost on this one**

3.) A ball is dropped from rest from the top of a cliff that is 27.6 m high. From ground level, a second ball is thrown straight upward at the same instant that the first ball is dropped. The initial speed of the second ball is exactly the same as that with which the first ball eventually hits the ground. In the absence of air resistance, the motions of the balls are just the reverse of each other. Determine how far below the top of the cliff the balls cross paths. ** totally lost***

4.) The three-toed sloth is the slowest moving land mammal. Assume that on the ground the sloth moves at an average speed of 0.013 m/s, considerably slower than the giant tortoise, which walks at 0.0193 m/s. After 20 minutes of walking, how much further would the tortoise have gone relative to the sloth?

** please help this homework is due tomorrow..thank you.. i'll buy you guys ice cream for helping me with the questions...
 
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Read in your textbook about the acceleration due to gravity.

This will help you on the first, second and third questions.

The fourth question is simply determine how far each animal can travel in the allotted time and the difference between these two numbers. (Read in your textbook about average speed and average velocity.)
 
v(t) = v_0 + \frac{1}{2} a t^2
i think this is the equation to use.
 
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