7, Explain why ethylated spirit at room temperature when dropped at the back of the palm makes the palm to feel very cold.
(2 Marks)

Of course the molecules need energy to escape and so the hotter the liquid becomes the ... If we put a drop of methylated spirit on our hand the methylated spirit will soon evaporate and our hand feels cold. ... As the ether evaporates pump into the air bubbles it takes away heat energy from the tube, lowering its temperature.

Explanation:

we're given that v₀ = 0 and a = 5.4 m/s². therefore, since v = at + v₀ for constant acceleration the equation for velocity is

after 28s,

m/s

which i would round to 150 m/s as my final answer

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