Explanation:
do we can say that the first step is finding the acceleration of the object. We do so by saying F = ma
so a = F/m
a = 500 m/s^2
we now have the time, acceleration and initial velocity.
so we can find the final velocity by using one of newtons equations which is: vf = vi + at
so:
vf = 0 + 500 × 12
vf = 6000
note that our initial velocity was zero since the object was initially at rest.
if you still have any doubt dont hesitate to ask for further help.
Answer:
D. Test a cell phone's reception in the exact same location under various atmospheric conditions
Explanation:
Components of an experiment:
Independent variable:
A manipulated variable, in an experiment or study, whose presence or degree incurs a change in the dependent variable.
Dependent variable:
A variable which is being studied in the experiment and is supposed to change with respect to the independent variable.
Control variable:
Control variable includes the variables which are of no concern in the experiment and must be constant so that they do not interfere with the results of the experiment. Change in control variable might affect the results of an experiment.
In Anna's experiment, the independent variable is the atmospheric conditions. The dependent variable is cell phone reception that will change according to the atmospheric conditions. All other things related to the experiment are control variables like cellphone, location of the cell phone. Both of these must stay constant to collect the best data.
Hence, the best option is D.
Answer:
It is a copy of an object and appears to be coming from behind the mirror.
Explanation:
- The plane mirror has a flat surface, where of its surface is polished to reflect the light.
- The plane mirror shows the image as the same size of the object.
- The image produced by the plane mirror is virtual and erect.
- But the orientation of the image formed changes the left and right.
- Hence,the image appears to be coming from behind the mirror.
Answer: d. I or II
Explanation: A traveling wave has speed that depends on characteristics of a medium. Characteristics like linear density (μ), which is defined as mass per length.
Tension or Force (
) is also related to the speed of a moving wave.
The relationship between tension and linear density and speed is ginve by the formula:
So, for the traveling waves generated on a string fixed at both ends described above, ways to increase wave speed would be:
1) Increase Tension and maintaining mass and length constant;
2) Longer string will decrease linear density, which will increase wave speed, due to their inversely proportional relationship;
Then, ways to increase the wave speed is
I. Using the same string but increasing tension
II. Using a longer string with the same μ and T.
