Not too long ago houses were protected from excessive currents by fuses rather than circuit breakers. sometimes a fuse blew out and a replacement wasn't at hand. because a copper penny happens to have almost the same diameter as a fuse, some people replaced the fuse with a penny. unfortunately, a penny never blows out, no matter how large the current, and the use of pennies in fu se boxes caused many house fires. make the appropriate measurements on a penn y, then calcul ate the resistance between the two faces of a solid-copper penny. (modern pennies have the same dimensions, but are made of zinc with a copper coating.)

Resistance =

The approximate diameter of a penny is, d = 20 mm

thickness of penny is, L = 1.5× mm

The area of penny along circular face is,

= 3.14× m²

The resistivity of copper is ρ = 1.72 x 10-8 Ωm.

Resistance,

gpe = mass x gravity constant x height or… gpe = mgh

where… mass: measured in kilograms (kg)

gravity: gravity constant on earth = 10.00 m/s2

height: measured in meters (m)

gpe: measured in joules (j) or kilojoules (kj)

how do you solve gpe?

gravitational potential energy (gpe) is the energy an object has because of its position above the. ground.

gpe = mass x gravity constant x height or… gpe = mgh.

mass:

note: to earn full marks when solving science word problems, you must show your work:

formula.

example:

given values:

mass = 0.3 kg.