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2 years ago

What is the mass number of a potassium atom that has 20 neutrons

1 answer:

6 0

<span>The mass of potassium is 39. This is obtained by adding the 19 protons and 20 neutrons found inside the nucleus</span>

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A solid weighs 16.5N on the surface of the moon. The force of gravity on the moon is 1.7N/Kg.

Fiesta28 [93]

Answer:

mass = 9.7 kg

Explanation:

Weight = Mass x Acceleration due to gravity (g)

16.5 = mass x 1.7

mass = $\frac{16.5}{1.7}$ = 9.7 kg

3 0

2 years ago

A string under a tension of 50.4 N is used to whirl a rock in a horizontal circle of radius 2.51 m at a speed of 21.1 m/s. The s

Leokris [45]

Answer:

619.8 N

Explanation:

The tension in the string provides the centripetal force that keeps the rock in circular motion, so we can write:

$T=m\frac{v^2}{r}$

where

T is the tension

m is the mass of the rock

v is the speed

r is the radius of the circular path

At the beginning,

T = 50.4 N

v = 21.1 m/s

r = 2.51 m

So we can use the equation to find the mass of the rock:

$m=\frac{Tr}{v^2}=\frac{(50.4)(2.51)}{21.1^2}=0.284 kg$

Later, the radius of the string is decreased to

r' = 1.22 m

While the speed is increased to

v' = 51.6 m/s

Substituting these new data into the equation, we find the tension at which the string breaks:

$T'=m\frac{v'^2}{r'}=(0.284)\frac{(51.6)^2}{1.22}=619.8 N$

5 0

3 years ago

Electric energy can be transferred into other types of energy we often experiences transformation of energy in our every day liv

Damm [24]

An amplifier.

Electrical energy provided to an amplifier is converted into sound energy as it is "fed" or provided to the speaker portion of an amplifier.

7 0

2 years ago

You have a double slit experiment, with the distance between the two slits to be 0.025 cm. A screern is 120 cm behind the double

dimulka [17.4K]

Answer:

The wavelength of the light is 633 nm.

Explanation:

Given that,

Distance between the two slits d= 0.025 cm

Distance between the screen and slits D = 120 cm

Distance between the slits y= 1.52 cm

We need to calculate the angle

Using formula of double slit

$\tan\theta=\dfrac{y}{D}$

Where, y = Distance between the slits

D = Distance between the screen and slits

Put the value into the formula

$\tan\theta=\dfrac{1.52}{120}$

$\theta=\tan^{-1}\dfrac{1.52}{120}$

$\theta=0.725$

We need to calculate the wavelength

Using formula of wavelength

$d\sin\theta=n\lambda$

Put the value into the formula

$0.025\times\sin0.725=5\times\lambda$

$\lambda=\dfrac{0.025\times10^{-2}\times\sin0.725}{5}$

$\lambda=6.326\times10^{-7}\ m$

$\lambda=633\ nm$

Hence, The wavelength of the light is 633 nm.

4 0

2 years ago

When we experience positive "g forces", it is as if we have become...

zhenek [66]

Answer:

heavier

Explanation:

7 0

2 years ago