The number of centimeters, d, that a spring is compressed from its natural, uncompressed position is given by the formula
where W is the number of joules of work done to move the spring and k is the spring constant. If a spring has a spring constant of 0.2, find the amount of work needed to move the spring 7 centimeters.
◦ 49 joules
◦ 4.9 joules
◦ 9.8 joules
◦ 0.7 joules