Ahydrogen atom has a diameter of about 9.95 nm. express this diameter in meters.

1 meter = 1,000,000,000 nanometers

OR

1 nanometer = 0.000000001 meters

so, to convert the diameter of a hydrogen atom in nanometers to meters, you just have to multiply

9.95 x 0.000000001 = 0.00000000995 nm

therefore the diameter of a hydrogen atom in meters is 0.00000000995m

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