An astronaut lands on an alien planet. he places a pendulum (l = 0.200 m) on the surface and sets it in simple harmonic motion, as shown in this graph.

answer the following questions:
what is the period and frequency of the pendulum’s motion?
how many seconds out of phase with the displacements shown would graphs of the velocity and acceleration be?
what is the acceleration due to gravity on the surface of the planet in m/s2? determine the number of g-forces.
show any necessary calculations.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia