A spring of spring constant k=8.25N/m is displaced from equilibrium by a distance of 0.150m. What is the stored energy in the form of spring potential energy? Show your work.

0.0928J

Explanation:

the pulling force of spring F=-kx

where x is the displacement from equilibrium position.

energy stored:

*** Its fine if you know nothing about calculus. Just apply the equation

  where U is the potential energy of the spring***

  put x=0.150, × = 0.0928J (corr. to 3 sig. fig.)

a small object of mass 3.66 g and charge -17.6 µc is suspended motionless above the ground when immersed in a uniform electric field perpendicular to the ground. what are the magnitude and direction of the electric field?

we need answer choices