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3 years ago

What is the total number of neutrons in an atom of an element that has a mass number of 19 and an atomic number of 9?

1 answer:

7 0

Your answer should be B.) 10

The atomic mass of an element is the sum of the element's protons and neutrons. The atomic number of an element is equal to its number of protons. To find the amount of neutrons in an atom, subtract the atomic number from the atomic mass. 19 - 9 = 10.

Hope this helps!

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You push a 85 kg shopping cart from rest with a net force of 250 n for 5 seconds,at which point it flies off a cliff that is 100

Vikki [24]

m = mass of the cart = 85 kg

F = net force on the cart = 250 N

a = acceleration of the cart

acceleration of the cart is given as

a = F/m

a = 250/85

a = 2.94 m/s²

t = time for which the force is applied = 5 sec

v₀ = initial velocity of the cart = 0 m/s

v = final velocity of the cart just before it flies off the cliff = ?

using the equation

v = v₀ + a t

inserting the values

v = 0 + (2.94) (5)

v = 14.7 m/s

consider the motion of cart after it flies off the cliff in vertical direction :

v' = initial velocity in vertical direction = 0 m/s

a' = acceleration in vertical direction = g = acceleration due to gravity = 9.8 m/s²

t' = time taken for the cart to land = ?

Y' = vertical displacement of the cart = height of cliff = 100 m

using the kinematics equation

Y' = v' t' + (0.5) a' t'²

100 = (0) t' + (0.5) (9.8) t'²

t' = 4.52 sec

consider the motion of cart along the horizontal direction after it flies off the cliff

X = distance traveled from the base of cliff = ?

t' = time of travel = 4.52 sec

v = velocity along the horizontal direction = 14.7 m/s

distance traveled from the base of cliff is given as

X = v t'

X = 14.7 x 4.52

X = 66.4 m

3 0

3 years ago

All electric devices are required to have identifying plates that specify their electrical characteristics. The plate on a certa

masha68 [24]

Answer:

R= 20 ohm

Explanation:

Given that

Current ,I = 6 A

Voltage difference ,ΔV = 120 V

Lets take resistance of the stem iron = R

We know that ,the relationship between current ,voltage difference and resistance is given as

ΔV = I R

$R=\dfrac{\Delta V}{I}$

Now by putting the values in the above equation we get

$R=\dfrac{120}{6}\ ohm$

R= 20 ohm

Therefore the resistance of the steam will be 20 ohm.

3 0

3 years ago

Type the correct answer in the box. use numerals instead of words. anne has a sample of a substance. its volume is 20 cm3, and i

CaHeK987 [17]

The density of sample is 5 g/cm3

Given:

volume of sample = 20 cm3

mass of sample = 100 grams

To Find:

density of sample

Solution: Density is the measure of how much “stuff” is in a given amount of space. For example, a block of the heavier element lead (Pb) will be denser than the softer, lighter element gold (Au). A block of Styrofoam is less dense than a brick. It is defined as mass per unit volume

density = mass/volume

d = 100/20

d = 5 g/cm3

So, density of sample is 5 g/cm3

Learn more about Density here:

brainly.com/question/1354972

#SPJ4

6 0

1 year ago

What is the radius of a circle thats the diameter of 480?

Luda [366]

The answer is 12.36. hoped this helped!