Answer:
<em>The second option has a lower power output. P=30 W</em>
Explanation:
<u>Mechanical Power
</u>
It is a physical magnitude that measures the rate a work W is done over time t.

Since W=F.d

The first option means the worker will lift the box by a distance of 1.2 meters in 3 seconds by applying 250 N of force. That produces a power of

The second option requires the worker applies 75 N of force and travel a distance of 4 meters for 10 seconds, thus the power is

The second option has a lower power output
Answer:
When the velocity doesn't change its direction
Explanation:
Since velocity vector has 2 components: direction and magnitude, and speed is the velocity's magnitude. So if the velocity doesn't change its direction, we essentially use its magnitude, aka speed, to calculate the rate of change for acceleration.
Answer:
B
Explanation:
Nuclear fission is the process of splitting apart nuclei. When nuclei fission energy is released. So much energy is released that there is a measurable decrease in mass, from the mass-energy equivalence. This means that some of the mass is converted to energy.
Answer:
The angular displacement of the wheel is 45 radians
Explanation:
Given;
initial angular velocity, ω₀ = 20 rad/s
final angular velocity, ωf = 10 rad/s
time interval, t = 5
Angular acceleration is calculated as;

|α| = 2 rad/s²
Angular displacement is calculated as;

Therefore, the angular displacement of the wheel is 45 radians
Back then, Robert Hooke found cells from a cork and named it cells. Later on, Matthias Schleiden found cells from plant parts and concluded that all plants are made of cells. Theodor Schwann, after observing many different animal cells, concluded that all animal have cells. Several years later, Rudolf Virchow hypothesized that cells divide to form new cells. Virchow proposed that every living organism has cells. His observations and conclusions and those of others are summarized in the cell theory