Two boxes m_1 and m_2 are connected by a lightweight cord and sitting on a frictionless surface. A horizontal force of 66 N pulls on box m_1 and then m_2 is pulled along.

If the acceleration of the boxes is 2.2 m/s^2 and the mass of m_1 is 12 kg. Find the mass of m_2.

a. 12 kg

b. 18 kg

c. 30 kg

d. 48 kg

e. 42 kg

heat the gas and measure the pressure

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

b. a lightning bug, plug of grass, and a worm