Q. A woman is reported to have fallen 144 ft from the 17th floor of a building, landing on a metal ventilator box, which she crushed to a depth of 18 in. She suffered only minor injuries. Neglecting air resistance, compute (a) The speed of the woman just before she collided with ventilator, (b) Her average acceleration while in contact with the box and (c) The time it took to crush the box.
Q. A 0.10kg solid rubber ball is attached to the end of a 0.80 m length of light thread. The ball is swung in a vertical circle. Point p, the lowest point of the circle, is 0.20 m above the floor. The speed of the ball at the top of the circle is 6m per second, and the total energy of the ball is kept constant. Resolve the total energy of the ball, using the floor as a zero point for gravitational potential energy. Find out the speed of the ball at point p, the lowest point of the circle.