Ask question

Ask question

All categories

VashaNatasha [74]

3 years ago

15

A friend tells you that a rowboat is propelled forward by the force of its oars against the water. First explain whether the sta

tement is correct and then identify the action and reaction forces

1 answer:

stellarik [79]3 years ago

7 0

It is correct, the action is paddling, where you move the water backwards, and the reaction is the boat moving forwards.

You might be interested in

A series circuit has a 12-volt power source and two resistors of 1 ohm and 2 ohms respectively. How many amps will flow when

Andrej [43]

Answer:

ayoooooooo

Explanation:

3 0

3 years ago

A series of optical telescopes produced an image that has a resolution of about 0.00350 arc second.

Mila [183]

Answer:

The smallest diameter is $D =122 \ m$

Explanation:

From the question we are told that

The resolution of the telescope is $\theta = 0.00350 \ arc \ second$

The wavelength is $\lambda = 1.70 \mu m = 1.70 *10^{-6} \ m$

From the question we are told that

$1 arc \ sec = \frac{1}{3600^o}$

So $0.00350 \ arc \ second = x$

Therefore

$x = 0.00350 * \frac{1}{3600 }$

$x = ( 9.722*10^{-7} )^o$

Now $1^o = \frac{\pi}{180}$

So $(9.722*10^{-7})^o = \theta$

=> $\theta = (9.722*10^{-7}) * \frac{\pi}{180}$

$\theta = 1.69*10^{-8} rad$

The smallest diameter is mathematically represented as

$D = \frac{1.22 \lambda }{\theta }$

substituting values

$D = \frac{1.22 * 1.7 *10^{-6}} {1.69 *10^{-8} }$

$D =122 \ m$

6 0

3 years ago

Why is it important to use placebos and a double-blind approach in some studies

viktelen [127]

Another name for these two words is "constant" and you want to have a "constant", because you want something to compare your experimental group to, to see whether data had changed or not. So you have placebos or a double- blind to compare your experimental group to it and also so you know you don't have a bias or anything in the study.

6 0

3 years ago

0.0884 moles of a diatomic gas

Sloan [31]

Answer:

W = - 118.24 J (negative sign shows that work is done on piston)

Explanation:

First, we find the change in internal energy of the diatomic gas by using the following formula:

$\Delta\ U = nC_{v}\Delta\ T$

where,

ΔU = Change in internal energy of gas = ?

n = no. of moles of gas = 0.0884 mole

Cv = Molar Specific Heat at constant volume = 5R/2 (for diatomic gases)

Cv = 5(8.314 J/mol.K)/2 = 20.785 J/mol.K

ΔT = Rise in Temperature = 18.8 K

Therefore,

$\Delta\ U = (0.0884\ moles)(20.785\ J/mol.K)(18.8\ K)\\\Delta\ U = 34.54\ J$

Now, we can apply First Law of Thermodynamics as follows:

$\Delta\ Q = \Delta\ U + W$

where,

ΔQ = Heat flow = - 83.7 J (negative sign due to outflow)

W = Work done = ?

Therefore,

$-83.7\ J = 34.54\ J + W\\W = -83.7\ J - 34.54\ J\\$

<u>W = - 118.24 J (negative sign shows that work is done on piston)</u>

7 0

3 years ago

Read 2 more answers

In your own words, explain how the red shift in the spectrum of objects in space provide evidence for the Big Bang Theory.

kondaur [170]

The evidence that the universe is expanding comes with something called the red shift<span> of light. Light travels to Earth from other galaxies. As the light from that galaxy gets closer to Earth, the distance between Earth and the galaxy increases, which causes the wavelength of that light to get longer.</span>

6 0

3 years ago

Read 2 more answers