Answer: D
Experiment 1 has a confounding variable related to the mass of the rockets. Any variation in mass may cause a discrepancy in the distance traveled.
This is the answer to the question because:
- Both experiments do have a confounding variable.
- Experiment 1 doesn't have to stay constant.
- A double-blind experiment will not do anything to the placebo.
- High blood pressure people will not make the results confusing.
The answer has to be the option D. Hope this helps you!
![using \: the \: formula \\ t = \frac{2u \sin( \alpha ) }{g} where \: u = initial \: speed \: \\ \alpha = angle \: of \: projection \\ g = acceleration \: due \: to \: gravity \\ \frac{2 \times 50 \times \sin(30) }{10} \\ \frac{100 \times 0.5}{10} = \frac{50}{10} = 5seconds](https://tex.z-dn.net/?f=using%20%5C%3A%20the%20%5C%3A%20formula%20%5C%5C%20t%20%3D%20%5Cfrac%7B2u%20%5Csin%28%20%5Calpha%20%29%20%7D%7Bg%7D%20where%20%5C%3A%20u%20%3D%20initial%20%5C%3A%20speed%20%5C%3A%20%5C%5C%20%5Calpha%20%3D%20angle%20%5C%3A%20of%20%5C%3A%20projection%20%5C%5C%20g%20%3D%20acceleration%20%5C%3A%20due%20%5C%3A%20to%20%5C%3A%20gravity%20%5C%5C%20%5Cfrac%7B2%20%5Ctimes%2050%20%5Ctimes%20%5Csin%2830%29%20%7D%7B10%7D%20%5C%5C%20%5Cfrac%7B100%20%5Ctimes%200.5%7D%7B10%7D%20%3D%20%5Cfrac%7B50%7D%7B10%7D%20%3D%205seconds)
Maximum height
= (Usinα)^2/2g
(50*0.5)^2/20
25^2/20
625/20
=31.25metres
horizontal distance = Range= [U^2 * sin2α]/g
[50^2 * sin60]/10
2500 * 0.8660/10
2165/10=216.5metres
Answer:
![\large \boxed{42\, \mu \text{C}}$](https://tex.z-dn.net/?f=%5Clarge%20%5Cboxed%7B42%5C%2C%20%5Cmu%20%5Ctext%7BC%7D%7D%24)
Explanation:
The formula for the force exerted between two charges is
![F=k \dfrac{ q_1q_2}{r^2}](https://tex.z-dn.net/?f=F%3Dk%20%5Cdfrac%7B%20q_1q_2%7D%7Br%5E2%7D)
where k is the Coulomb constant.
The charges are identical, so we can write the formula as
![F=k\dfrac{q^{2}}{r^2}](https://tex.z-dn.net/?f=F%3Dk%5Cdfrac%7Bq%5E%7B2%7D%7D%7Br%5E2%7D)
![\begin{array}{rcl}\text{4.0 N}& = & 8.988 \times 10^{9}\text{ N$\cdot$m$^{2}$C$^{-2}$} \times \dfrac{q^{2}}{\text{(2.0 m)}^{2}}\\\\4.0 & = & 2.25 \times 10^{9}\text{ C$^{-2}$} \times q^{2}\\\\q^{2} & = & \dfrac{4.0}{2.25 \times 10^{9}\text{ C$^{-2}$}}\\\\& = & 1.78 \times 10^{-9} \text{ C}^{2}\\q & = & 4.2 \times 10^{-5} \text{ C}\\& = & 42\, \mu \text{C}\\\end{array}\\\text{Each charge has a value of $\large \boxed{\mathbf{42\, \mu }\textbf{C}}$}](https://tex.z-dn.net/?f=%5Cbegin%7Barray%7D%7Brcl%7D%5Ctext%7B4.0%20N%7D%26%20%3D%20%26%208.988%20%5Ctimes%2010%5E%7B9%7D%5Ctext%7B%20N%24%5Ccdot%24m%24%5E%7B2%7D%24C%24%5E%7B-2%7D%24%7D%20%5Ctimes%20%5Cdfrac%7Bq%5E%7B2%7D%7D%7B%5Ctext%7B%282.0%20m%29%7D%5E%7B2%7D%7D%5C%5C%5C%5C4.0%20%26%20%3D%20%26%202.25%20%5Ctimes%2010%5E%7B9%7D%5Ctext%7B%20C%24%5E%7B-2%7D%24%7D%20%5Ctimes%20q%5E%7B2%7D%5C%5C%5C%5Cq%5E%7B2%7D%20%26%20%3D%20%26%20%5Cdfrac%7B4.0%7D%7B2.25%20%5Ctimes%2010%5E%7B9%7D%5Ctext%7B%20C%24%5E%7B-2%7D%24%7D%7D%5C%5C%5C%5C%26%20%3D%20%26%201.78%20%5Ctimes%2010%5E%7B-9%7D%20%5Ctext%7B%20C%7D%5E%7B2%7D%5C%5Cq%20%26%20%3D%20%26%204.2%20%5Ctimes%2010%5E%7B-5%7D%20%5Ctext%7B%20C%7D%5C%5C%26%20%3D%20%26%2042%5C%2C%20%5Cmu%20%5Ctext%7BC%7D%5C%5C%5Cend%7Barray%7D%5C%5C%5Ctext%7BEach%20charge%20has%20a%20value%20of%20%24%5Clarge%20%5Cboxed%7B%5Cmathbf%7B42%5C%2C%20%5Cmu%20%7D%5Ctextbf%7BC%7D%7D%24%7D)
There are NO true statements on that list of choices.
This question is asking you to determine if individual atoms or systems, or both have these types of energy. A system would be "all the molecules or atoms" whereas an individual atom is "each of the molecules or atoms."
Answers:
A. All the molecules or atoms in motion have kinetic energy.
B. Each molecule or atom in motion has kinetic energy.
D. All the molecules or atoms in motion have thermal energy.
The only incorrect answer is C because individual atoms don't have thermal energy, only when they interact with other atoms. Still, atoms do have kinetic energy, which has the potential to turn into heat energy in these interactions.
Hope this helps!