A clock draws 2.0 watts of power to operate and is in operation 8,600 hours per year. The energy usage of the clock, in kWh per year, is closest to

the energy usage of the clock per year is 17.2 kWh

Explanation:

Given;

power drawn by the clock, P = 2 W

duration of the clock's operation, t = 8,600 hours per year

The energy usage of the clock per year is calculated as;

E = Pt

Therefore, the energy usage of the clock per year is 17.2 kWh

force tends to be low and long diustance masses are high

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