These are questions from my previous tests within this semester that I didn't exactly get correct. I can't seem to figure them out/find an example, nor is my teacher going to be available before my exam. So here I am. I need to know how to solve them, and them to be solved. These are not homework or assignment problems, these are just very plausible problems for the exam that I want to understand.(adsbygoogle = window.adsbygoogle || []).push({});

1) A football quarterback attempts a pass to one of the receivers. As the ball is snapped, the reciever leaves the line of scrimmage and runs directly down field. The quarterback releases the ball 2.0s later and from a position 3.0m behind the line of scrimmage. He throws the ball with a speed of 26m/s at an elevation of 60degrees above the horizontal. The reciever makes the diving reception, catching the ball just as it reaches the ground. The quarterback is 2.0m tall *where the ball is released*

a) What is the time of flight of the football?

b) What is the average speed of the receiver?

2) A rock of mass 4.0 * 10^2g is tied to one end of a string that is 2.0m in length. Holding the other end above his head, a boy swings the rock around in a circle whose plane is parallel to the ground.

a) If the string can withstand a maximum tension of 4.5N before breaking, what angle to the vertical does the string reach just before breaking?

b) At what speed is the rock travelling just as the string breaks?

3) A helicopter is rising vertically at a uniform velocity of 14.7m/s. When it is 196m from the ground, a ball is projected from it with a horizontal velocity of 8.5m/s with respect to the helicopter. Calculate the following.

a) When the ball will reach the ground?

b) Where it will hit the ground?

c) What its velocity will be when it hits the ground?

Again, please put how it was done. Any help is appreciated. Thanks a lot.

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# Homework Help: Possible Exam question

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