What colors form the spectrum of visible light

What is the weight of a 48kg rock?

IrinaK [193]

Answer:

48kg

Explanation:

4 0

2 years ago

An electromagnetic wave of intensity 150 W/m2 is incident normally on a rectangular black card with sides of 25 cm and 30 cm tha

LenKa [72]

Answer:

3.75 × 10⁻⁸ N

Explanation:

Given:

Intensity of the electromagnetic wave, I = 150 W/m²

Sides of the board = 25 cm (= 0.25 m) and 30 cm (= 0.30 m)

therefore,

the area of the rectangular box, A = 0.25 × 0.30 = 0.075 m²

Now,

force exerted on the card by the radiation, F = $\frac{IA}{C}$

here,

C is the speed of the light = 3 × 10⁸ m/s

on substituting the respective values, we get

F = $\frac{150\times0.075}{3\times10^8}$

or

F = 3.75 × 10⁻⁸ N

5 0

2 years ago

A soccer player kicks a rock horizontally off a 37 m high cliff into a pool of water. If the player hears the sound of the splas

Alchen [17]

<h2>Answer:</h2>

(a). 16.741 m/s

(b). 15.75 m/s

<h2>Explanation:</h2>

In the question,

Height of the cliff, h = 37 m

Time taken to reach the sound to us = 2.92 s

Speed of the sound in air at room temperature = 343 m/s

Now,

Let us say the speed of the ball = u m/s

So,

Time taken by the ball to reach at the bottom, t is given by,

$t=\sqrt{\frac{2h}{g}}\\t=\sqrt{\frac{2\times 37}{9.8}}\\t=2.747\,s$

So,

Splash is heard after = 2.92 s

So,

Time taken by sound to travel the shortest distance along the hypotenuse of the triangle thus formed is,

t = 2.92 - 2.747

t = 0.172 s

Now,

Distance traveled by sound is given by,

$Distance=343\times 0.172\\Distance=59.02\,m$

So,

In the triangle using the Pythagoras Theorem,

Horizontal distance traveled is,

$D=\sqrt{59.02^{2}-37^{2}}\\D=45.99\,m$

So,

Speed of throwing of ball is given by,

$Distance=Speed\times Time\\45.99=u\times 2.747\\u=16.741\,m/s$

Therefore, the speed of the ball = 16.741 m/s.

(b).

If,

Speed of sound = 331 m/s

So,

Distance traveled by sound is,

$Distance=331\times 0.172\\Distance=56.932\,m$

So,

Distance traveled in the horizontal by ball is,

$Distance=\sqrt{56.932^{2}-37^{2}}\\Distance=43.269\,m$

So,

Speed of the ball thrown is given by,

$Speed=\frac{Distance}{Time}\\Speed=\frac{43.269}{2.747}\\Speed=15.75\,m/s$

Therefore, the speed of the ball = 15.75 m/s.

8 0

3 years ago

Some students set up a circuit and decided to measure the voltage at different points around

Fiesta28 [93]

Answer:

V₁ = 6 V , V₂ = V₃ = 3 V

Explanation:

To solve this circuit we must remember that there are two fundamental types of construction in series and parallel.

* a serial circuit there is only one path for current

in this circuit the constant current in the entire circuit and the voltage is the sum of the voltage of each term

* Parallel circuit in this there are two or more paths for the current

in this circuit the voltage is constant and the east is divided between each branch

with these principles let's analyze the proposed circuit

The DC battery is in parallel with resistor R1 and the equivalent of the other branch,

as in a parallel circuit the voltage is constant

V₁ = 6 V

in the other branch (23) it forms a series construction, where the current is constant

6 = iR₂ + iR₃

as they indicate that each resistance has the same value

6 = 2 iR

V = V₂ = V₃ = 3 V

3 0

2 years ago

Sarah wants to install a wind turbine on her farm, which would convert wind energy to electricity to power her home. She can onl

Marina86 [1]

Answer:

The best choice would be c

Explanation: Sarah wants this wind turbine to efficient since she can only get one. C has the most reasonable option data collected will help her know the best wind speed over her farm.

6 0

2 years ago

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