Physics students are testing an old bed spring which is compressed 4cm when a force of 4 N is applied. This spring is secured to a wall and a bowling ball of 4kg is roled into it so that it hits at a speed of 2m/s(adsbygoogle = window.adsbygoogle || []).push({});

1. Calculate the compression of the spring when the speed of the ball has been reduced to 1m/s by the spring

2. What is the value of the compression force when the speed of the ball is 1.9 ms to the right?

3. Calculate the compression of the spring what the ball has momentarily come to rest.

For the first question:

the kinetic energy of the ball at 2ms = .5 * 4 * (2 squared) = 8 N

the kinetic energy of the ball at 1ms = .5 * 4 * (1 squared) = 2 N

thus the kinetic energy transfered to the spring is 6 N

Now, .5k(x squared) gives us the potential energy in the spring.

so 6 = .5k(x squared)

k is the spring ocnstand which can be taken from 4N/.04 Meters = 100

6 = 50(x squared)

X = Square root of (6/50)

= .346 meters = 34.6 cm?

thats all i can get at the mo..i need help :)

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