Work done is given by the change in kinetic energy of an object
- The kinetic energy of the shovel, the shrub, and in Robert's movement were changed, therefore, work is done in the given processes,
Reason:
Work is done when the total energy of object is affected by the application of force on the object over a distance
Therefore;
- In option <em>A</em>, pushing the shovel into ground (to dig out the dirt) the requires the application of a force (push) over a distance, (into and out of the ground) therefore work is done
- In option <em>B</em>, picking the shrub up gives it gravitational potential energy, therefore, work is done
- In option <em>C</em>, carrying the shrub to the hole does visible work
- In option <em>D</em>, holding the shrub while lowering it into the hole does work by preventing the shrub from falling randomly
Therefore, <u>work is done in the given processes</u>
Learn more about work-energy theorem here:
brainly.com/question/10063455
Answer:
540m/s
Explanation:
Given parameters:
Frequency of the wave = 18000Hz
Wavelength of the wave = 0.03m
Unknown:
How fast is the wave traveling = ?
Solution:
How fast the wave is traveling is a measure of the speed of the wave;
Speed of wave = frequency x wavelength
Now insert the given parameters and solve;
Speed of wave = 18000 x 0.03 = 540m/s
Answer:
Input power, Ip = 4 Watts
Explanation:
Given the following data;
Power output = 0.8 Watts
Efficiency = 20%
To find the power input of the sunlight onto the solar panel;
Mathematically, the efficiency of a machine is given by the formula;
Substituting into the formula, we have;
Cross-multiplying, we have;
Input power, Ip = 4 Watts
