A 0.5 kg ball is rolling down a hill going at 4 m/s. How much force is acting on the ball if it rolled for 5 m?

no. dot product   =0 when vecs at right angles

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

the given statement is true.

sensory memory lasts for a fraction of seconds before the information is lost. it is the shortest -term memory and can be called as an element of memory. example: when we look at something and remember what it looks like, is just a second of observation. it degrades very quickly. it can also be considered as the process of perception rather than considering it as a memory.