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3 years ago

What is the surface temperature of a star that has a peak wavelength of 290 nm?

1 answer:

5 0

We need to use Wien's Law

Wavelength = 0.0028976 [m.K] / T

This establishes a relation between the wavelength and temperature of a black body (any body that absorbs radiation, such as the stars)

T = 0.0028976 [m.K]/290 E-9[m] = 9991.724 K

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What type of convergent boundary is the himalayan mountains formed by

Diano4ka-milaya [45]

The Himalayan Mountains formed at a convergence plate boundary between the Eurasian plate and the Indian plate.

8 0

3 years ago

In a plate glass factory, sheets of glass move along a conveyor belt at a speed of 15.0 cm/s. An automatic cutting tool descends

Leni [432]

Answer:

angle at which the cutter should be set = 32°

Explanation:

We are given;

Speed of conveyor belt; v1 = 15 cm/s

Width;w = 72 cm

Speed of the cutter that moves across the width; v2 = 24 cm/s

Let's calculate time;

Since the width and the rate at which the cutter works per seconds is given, thus;

Time = w/v2

Time = 72/24 = 3 seconds

Now, we know that, velocity = distance/time

Thus, distance = velocity x time

So, distance covered;d = 15 x 3 = 45 cm

Now, for us to calculate the angle the cutter should be set, we would treat it as a triangle.

When the cutter cuts it, it covers a distance d which is perpendicular to the width.

Thus, to calculate the angle made with the width, we'll use trigonometric ratio.

Thus, d/w = tan θ where θ is the angle at which the cutter should be set.

So, 45/72 = tan θ

tan θ = 0.625

θ = tan^(-1)0.625

θ = 32°

3 0

3 years ago

A person wishes to heat pot of fresh water from 20°C to 100°C in order to boil water for pasta. They calculate that their pot ho

nasty-shy [4]

Given:
Water, 2 kilograms
T1 = 20 degrees Celsius, T2 = 100 degrees Celsius.

Required:
Heat produced

Solution:
Q (heat) = nRT = nR(T2 = T1)
Q (heat) = 2 kilograms (4.184 kiloJoules per kilogram Celsius) (100 degrees Celsius – 20 degrees Celsius)
<u>Q (heat) = 669.42 Joules
</u>This is the amount of heat produced in boiling 2 kg of water.

6 0

3 years ago

If a certain mass of mercury has a volume of 0.002m3 at a temperature of 20°C, what will be the volume at 50°C,

USPshnik [31]

Set this up as a proportion.

.002 m^3/20 degrees = x/50 degrees

solve for x

x = .005 m^3

If you found this helpful, please brainliest me!

3 0

3 years ago

What potential difference is needed to give a helium nucleus (q=2e) 85.0 kev of kinetic energy?

Vilka [71]

The kinetic energy K given to the helium nucleus is equal to its potential energy, which is
$E=q \Delta V$
where q=2e is the charge of the helium nucleus, and $\Delta V$ is the potential difference applied to it.
Since we know the kinetic energy, we have
$E=K=85~keV=q \Delta V$
and from this we can find the potential difference:
$\Delta V = \frac{K}{q}= \frac{85~keV}{2e}=42.5~kV$

6 0

3 years ago