A: Some physical properties change, but the substance keeps its identity.
True, recycling allows products to be reused which saves alot the natural resources that are used.
Explanation:
(a) E = F/q
E = 4.8×10^-17/1.6×10^-19
E = 300 N/C
(b) same magnitude of electric field is exerted on proton
Answer:
310.5 J
Explanation:
The total work done by Martha is equal to the increase in gravitational potential energy of the package, which is equal to

where
(mg) = 45 N is the weight of the package
is the increase in height of the package
The package is carried up 3 flights of stairs, each one with a height of 2.3 m, so the total increase in heigth is

And so, the work done by Martha is
