A penny is made of the element zinc plated with the element copper; a nickel
is made of a mixture of the elements
nickel and copper. Some isotopes of
various elements are listed below by
their atomic number and mass num-
ber. Use the periodic table on p. 131
to identify which atoms you would
expect to find in the penny, which you
would expect to find in the nickel,
which you would expect to find in
both, and which you would expect to
find in neither coin.​

d

explanation:

v=uf/(u-f)

= 5.10/(5-10) convex lens has positive focal length

=50/-5

=-10 cm (formed at other side)

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s