First, we calculate the mass of Phosphorous present:
283.88 x 0.4364
= 123.88 amu
Atomic mass of P is 31 amu

moles of P = mass / Ar
= 123.88 / 31
= 4.0 moles

We know that one mole of substance has 6.02 x 10²³ particles
Atoms of P = 4 x 6.02 x 10²³
= 2.41 x 10²⁴ atoms

6 0

3 years ago

Emily holds a banana of mass m over the edge of a bridge of height h. She drops the banana and it falls to the river below. Use

bearhunter [10]

Answer:

The mass of the banana is m and it is at height h.

Applying the Law of Conservation of Energy

Total Energy before fall = Total Energy after fall

$E_{i}$ = $E_{f}$

Here, total energy is the sum of kinetic energy and potential energy

$K.E_{i}$ + $P.E_{i}$ = $K.E_{f}$ + $P.E_{f}$ (a)

When banana is at height h, it has

$K.E_{i}$ = 0 and $P.E_{i}$ = mgh

and when it reaches the river, it has

$K.E_{f}$ = 1/2m $v^{2}$ and $P.E_{f}$ = 0

Putting the values in equation (a)

0 + mgh = 1/2m $v^{2}$ + 0

mgh = 1/2m $v^{2}$

<em>cutting 'm' from both sides</em>

<em> </em>gh = 1/2 $v^{2}$

v = $\sqrt{2gh}$

Hence, the velocity of banana before hitting the water is

v = $\sqrt{2gh}$

5 0

3 years ago

A floating ice block is pushed through a displacement d = (13.5 m)i + (-14.3 m)j along a straight embankment by rushing water, w

fredd [130]

To solve this problem, we are going to use the formula for work which is Fd where x and y are measured separately.

X direction: W = 13.5 x 230 = 3105 Joules

Y direction: W = -14.3 x -165 = 2360 Joules

So the total work is getting the sum of the two: 3105 + 2360 = 5465 Joules

7 0

3 years ago

a 60kg rock in on a mountain in banff national park breaks free from a ledge and falls down 500 meters to the bottom of the moun

stellarik [79]

Using Newton's law that F = ma.

The force here is the net force. The forces acting in opposite direction are the weight and the air resistance. The weight of course is acting downwards and the air resistance is pushing upwards.

Therefore:

W - AR = ma W = Weight = mg, AR = Air Resistance = 150.
g = 10 m/s2
mg - AR = ma

60(10) - 150 = 60a
600 - 150 = 60a
450 = 60a
60a = 450
a = 450/60
a = 7.5 m/s2

Cheers.

5 0

4 years ago