Answer:
V = 26.95 cm³
Explanation:
Density is given by the formula :
ρ = m÷V
Density = mass ÷ Volume
Given both density and mass we rearrange, substitute and solve for Volume :
Rearranging the equation to make Volume the subject :
ρ = m÷V
ρV = m
V = m÷ ρ
Now substitute :
V = 45 ÷ 1.67
V = 26.9461077844
Take 2 decimal places as the density is 2 decimal places :
V = 26.95
Units will be cm³ as it is volume
Hope this helped and have a good day
The relationship between the number of visible spectral lines are identical for atoms .However they have unique wavelengths.
Option B
<u>
Explanation:</u>
A spectrum is a range of frequencies or a range of wavelengths. The photon energy of the emitted photon is equal to the difference between two states. For every atom there are quite many electron transitions and each has a energy difference.
This difference in wavelength causes spectrum .As each element emission spectrum is unique because each atom has different energy and causes uniqueness in the emission spectrum . Hence, due to the difference in energy it emits different wavelengths.
Force = mass x acceleration
Force = 4kg x 10m/s^2
Force = 40N
Answer:
<h2>1) there is no work done on the system</h2><h2>2) A) Using a lever to lift 100 newtons up to 4 meters on to a shelf</h2><h2 /><h2>3) P = 140 W</h2><h2>4) D) In a closed system, a system that isolated from its surrounds, the total energy of the system is conserved</h2>
Explanation:
1) As we know that work done is the product of force and the displacement of the point of action where force is applied
So here we have

as there is no displacement in the direction where the force is applied
2)As we know that work is product of force and displacement
So we will have




So maximum work is done on
A) Using a lever to lift 100 newtons up to 4 meters on to a shelf
3)
As we know that power is rate of work done
so we have



4)
As per energy conservation we know that
D) In a closed system, a system that isolated from its surrounds, the total energy of the system is conserved