A ping-pong ball weighs 0.025 N. The ball is placed inside a cup that sits on top of a vertical spring. If the spring is compressed 0.055 m and released, the maximum height above the compressed position that the ball reaches is 2.84 m. Neglect air resistance and determine the spring constant.

Explanation:

The energy stored in the spring is used to throw the ball upwards . Let the height reached be h

stored energy of spring = 1/2 k y² , k is spring constant and y is compression created in the spring

stored energy of spring = potential energy of the ball

1/2 k y² = mgh , m is mass of the ball , h is height attained by ball

.5 k x .055² = .025  x 2.84

.0015125 k = .071

k = .071 / .0015125

= 46.9 N / m .

area of focus

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