Gravitational potential energy can be described as m*g*h (mass times gravity times height).
Originally,
15kg * 9.8m/s^2 *0.3 m = 44.1 kg*m^2/s^2 = 44.1 Joules.
After it is moved to a 1m shelf:
15kg * 9.8m/s * 1 = 147 kg*m^2/s^2= 147 Joules.
To find how much energy was added, we subtract final energy from initial energy:
147 J - 44.1 J = 102.9 Joules.
Answer:
103.57 Km/h
Explanation:
From the question given above, the following data were obtained:
Distance = 725 Km
Time = 7 hours
Speed =?
Speed can be defined as the distance travelled per unit time. Mathematically, it is expressed as:
Speed = Distance /time
With the above formula, we can calculate how fast he will drive (i.e the speed) in order to get there on time. This is illustrated below:
Distance = 725 Km
Time = 7 hours
Speed =?
Speed = Distance /time
Speed = 725 / 7
Speed = 103.57 Km/h
Thus, to get there on time, he will drive with a speed of 103.57 Km/h
Speed uses distance and velocity uses displacement in its calculation.
For 100 m race, distance = displacement. Hence speed = velocity
For 400m race, distance ≠ displacement. distance = 400m whereas displacement = 0m. Hence speed ≠ velocity