A crane with output power of 200W will lift a 600N object a vertical distance of 4.0 meters in seconds

In an experiment to measure the wavelength of light using a double slit, it is found that the fringes are too close together to

Mandarinka [93]

Answer:

halve the slit separation

Explanation:

As we know that

In YDS experiment, the equation of fringe width is as follows

$\beta = \frac{\lambda D}{d}$

where,

D denotes the separation in the middle of screen and slits

d denotes the distance in the middle of two slits

And to increase the Δx we have to decrease the d i.e, the distance between the two slits

Hence, the first option is correct

4 0

2 years ago

A sharp edged orifice with a 50 mm diameter opening in the vertical side of a large tank discharges under a head of 5m. If the c

Sever21 [200]

Answer:

0.24

Explanation:

See attached file

3 0

2 years ago

You apply the brakes of your car abruptly and your book starts sliding off the front seat. Three observers sitting in the car ex

krek1111 [17]

Answer:

All the observers are correct.

Explanation:

This is simply a problem of reference frames from which the motion of the book is being viewed by the various observers.

From their various reference frames, they are all correct.

Observer A must be in the inertial reference frame.

Observers who can explain the behavior of the book and the car by using the relationship between the sum of the forces and changing velocity are said to be observers in inertial reference frames.

This is clearly shown by what observer A noticed. There was a relative motion between the book and the car as she pointed out, making her to be in an inertial reference frame.

Similarly, observers in inertial reference frames can also explain the changes in velocity of objects by considering the forces exerted on them by other objects.

This is shown by observer B as he is able to notice how the force of the car affects the velocity of the book.

Observer C is actually in a non-inertial reference frame, as newtons law of force motion relationship are no longer observed. This occurs in the non inertial reference frame.

7 0

2 years ago

Two parallel co-axial disks are floating in deep space (far from sun and planets). Each disk is 1 meter in diameter and the disk

HACTEHA [7]

Answer:

T₂ = 5646 K

Explanation:

Let's start by finding the power received by the first disc, for this we use Stefan's law

P = σ. A e T⁴

Where next is the Stefam-Bolztmann constant with value 5,670 10-8 W / m² K⁴, A is the area of the disk, T the absolute temperature and e the emissivity that for a black body is 1

The intensity is defined as the amount of radiation that arrives per unit area. For this we assume that the radiation expands uniformly in all directions, the intensity is

I = P / A

Writing this expression for both discs

I₁ A₁ = I₂ A₂

I₂ = I₁ A₁ / A₂

The area of a sphere is

A = 4π r²

I₂ = I₁ (r₁ / r₂)²

r₂ = r₁ ± 5

I₁ = I₂ ( (r₁ ± 5)/r₁)²

.

Let's write the Stefan equation

P / A = σ e T⁴

I = σ e T⁴

This is the intensity that affects the disk, substitute in the intensity equation

σ e₁ T₁⁴ = σ e₂ T₂⁴ (r₂ / r₁)²

The first disc indicates that it is a black body whereby e₁ = 1, the second disc, as it is painted white, the emissivity is less than 1, the emissivity values of the white paint change between 0.90 and 0.95, for this calculation let's use 0.90 matt white

e₁ T₁⁴ = T₂⁴ (r1 + 5)²/r₁²

T₁ = T₂ {(e₂/e₁)}^{1/4} √(1 ± 1/ r₁)

If we assume that r₁ is large, which is possible since the disks are in deep space, we can expand the last term

(1 ±x) n = 1 ± n x

Where x = 5 / r₁ << 1

We replace

T₁ = T₂ {(e₂/e₁)}^{1/4} (1 ± ½ 5/r1)

T₁ = T₂ {(e₂)}^{1/4} (1 ± 5/2 1/r1)

If the discs are far from the star, they indicate that they are in deep space, the distance r₁ from being grade by which we can approximate; this is a very strong approach

T₁ = T₂ {(e₂)}^{1/4} ¼

T₁ = T₂ 0.9 $0.9^{1/4}$