All categories

3 years ago

Which receptor cells most directly enable us to distinguish different wavelengths of light?

1 answer:

4 0

There are three main types of photoreceptor cells in the retinas of mammals: rods, cones and ganglion cells. Moreover, the ability to distinguish different wavelengths of visible light is the same as the ability to see color. This ability is provided by cone cells. Although cones are less sensitive to light than rods are, they allow us to distinguish different colors.<span />

You might be interested in

A grasshopper leaps into the air at a 62° angle above the horizontal, and follows a parabolic arc in free fall after it leaves t

harina [27]

Answer:

d. None of the above.

Explanation:

In a parabolic motion, you have that in the complete trajectory the component velocity is constant and the vertical component changes in time. Then, the total velocity vector is not zero.

In the complete trajectory the gravitational acceleration is always present. Then, the grasshopper's acceleration vector is not zero.

At the top of the arc the grasshopper is not at equilibrium because the gravitational force is constantly acting on the grasshopper.

Then, the correct answer is:

d. None of the above.

5 0

3 years ago

A soccer ball is kicked from the top of one building with a height of H1 = 30.2 m to another building with a height of H2 = 12.0

viktelen [127]

Hi there!

Initially, we have gravitational potential energy and kinetic energy. If we set the zero-line at H2 (12.0m), then the ball at the second building only has kinetic energy.

We also know there was work done on the ball by air resistance that decreased the ball's total energy.

Let's do a summation using the equations:
$KE = \frac{1}{2}mv^2 \\\\PE = mgh$

Our initial energy consists of both kinetic and potential energy (relative to the final height of the ball)

$E_i = \frac{1}{2}mv_i^2 + mg(H_1 - H_2)$

Our final energy, since we set the zero-line to be at H2, is just kinetic energy.

$E_f = \frac{1}{2}mv_f^2$

And:
$W_A = E_i - E_f$

The work done by air resistance is equal to the difference between the initial energy and the final energy of the soccer ball.

Therefore:
$W_A = \frac{1}{2}mv_i^2 + mg(H_1 - H_2) - \frac{1}{2}mv_f^2$

Solving for the work done by air resistance:
$W_A = \frac{1}{2}(.450)(15.1^2)+ (.450)(9.8)(30.2 - 12) - \frac{1}{2}(.450)(19.89^2)$

$W_A = \boxed{42.552 J}$

8 0

2 years ago

Can someone please help me come up with a hypothesis?. The question that I have is "How many sugars are in your smoothies?"

patriot [66]

'I believe that there is 20 grams of sugar in the smoothies.'

I don't know, just an idea.

8 0

4 years ago

Read 2 more answers

From mechanics, you may recall that when the acceleration of an object is proportional to its coordinate, d2xdt2=−kmx=−ω2x , suc

marysya [2.9K]

Answer:

q = q₀ sin (wt)

Explanation:

In your statement it is not clear the type of circuit you are referring to, there are two possibilities.

1) The circuit of this problem is a system formed by an Ac voltage source and a capacitor, in this case all the voltage of the source is equal to the voltage at the terminals of the capacitor

ΔV = Δ $V_{C}$

we assume that the source has a voltage of the form

ΔV = ΔV₀o sin wt

The capacitance of a capacitor is

C = q / ΔV

q = C ΔV sin wt

the current in the circuit is

i = dq / dt

i = c ΔV₀ w cos wt

if we use

cos wt = sin (wt + π / 2)

we make this change by being a resonant oscillation

we substitute

i = w C ΔV₀ sin (wt + π/2)

With this answer we see that the current in capacitor has a phase factor of π/2 with respect to the current

2) Another possible circuit is an LC circuit.

In this case the voltage alternates between the inductor and the capacitor

V_{L} + V_{C} = 0

L di / dt + q / C = 0

the current is

i = dq / dt

they ask us for a solution so that

L d²q / dt² + 1 / C q = 0

d²q / dt² + 1 / LC q = 0

this is a quadratic differential equation with solution of the form

q = A sin (wt + Ф)

to find the constant we derive the proposed solution and enter it into the equation

di / dt = Aw cos (wt + Ф)

d²i / dt²= - A w² sin (wt + Ф)

- A w² + 1 /LC A = 0

w = √ (1 / LC)

To find the phase factor, for this we use the initial conditions for t = 0

in the case of condensate for t = or the charge is zero

0 = A sin Ф

Ф = 0

q = q₀ sin (wt)

6 0

3 years ago

A person hits a tennis ball with a mass of 0.058 kg against a wall.

horrorfan [7]

Explanation:

Mass of the ball, m = 0.058 kg

Initial speed of the ball, u = 11 m/s

Final speed of the ball, v = -11 m/s (negative as it rebounds)

Time, t = 2.1 s

(a) Let F is the average force exerted on the wall. It is given by :

$F=\dfrac{m(v-u)}{t}$

$F=\dfrac{0.058\times (11-(-11))}{2.1}$

F = 0.607 N

(b) Area of wall, $A=3\ m^2$

Let P is the average pressure on that area. It is given by :

$P=\dfrac{F}{A}$

$P=\dfrac{0.607\ N}{3\ m^2}$

P = 0.202 Pa

Hence, this is the required solution.

8 0

3 years ago