1. Independent variable: the variable that can be modified and regulated.
the nail polish on Sarah's nails
2. Dependent variable: outcomes that result from the changes in the independent variable.
the duration of the nail polish's longevity
3. <span> Hypothesis: Different brands of nail polish have varied durations before they chip.
</span> 4. Control group: the <span> independent variable remains unchanged in this setup, not subject to variations.
</span> the schedule of when Sarah applies her nail polish (Sarah colors her nails every Sunday for a month)
the specific base coat and top coat (she <span> applies the same bottom coat and top coat with every kind of nail polish)
weekly habits (she ensures the same routine each week so her nails are not treated more harshly on some weeks).
</span> Experimental group: <span> the independent variable is altered for this group
type of nail polish (Essie, OPI, and Sally Hansen)
</span> 6. Constants: the experimenter (Sally), duration of study (one week), her weekly routine, <span> base coat and top coat, </span>
The overall force acting on the vehicle is zero
Explanation:
Let's evaluate the situation separately for the vertical direction and the horizontal direction along the slope.
Considering the direction perpendicular to the slope, two forces are in effect:
- The weight component acting perpendicular to the slope,
, directed into the slope - The normal force N, directed outward from the slope
Equilibrium exists here, indicating the net force in this direction is zero.
Now let’s examine the parallel direction to the slope. We have two forces present:
- The weight component aligned with the slope,
, directed down the slope - The frictional force
, acting up the slope
The car moves at a constant speed in this direction, indicating that its acceleration is zero.
Thus, according to Newton's second law,
implying the net force is zero:
Learn more about slopes and friction:
