You attach a cart with a mass of 2.6 kg to a spring and compress the cart-spring system so that the cart is located 40 cm behind the springs equilibrium point. If the cart is released and has a velocity of 2.0 m/s when it reaches the equilibrium position, what is the spring constant k?

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg