Answer:

Explanation:
Given data
mass of copper m=4.85 kg
charge of electron qe= -1.6×10⁻¹⁹C
To find
Number of electron n must be removed
Solution
Equate the magnitude of electric force Fe of repulsion between two two spheres to the magnitude of gravitational force of attraction between them
So

where q is charge of each sphere which is equal to number n of removed electrons multiplied by each charge qe
So

Answer:
i think its his law of inertia
Explanation:
this law is about motion
evaporation (if that's to fill in the blanks question)
Answer:
3100 m/s
Explanation:
The relationship between frequency and wavelength of a wave is given by the wave equation:

where
v is the speed of the wave
f is its frequency
is the wavelength
For the wave in this problem,
f = 15,500 Hz

Therefore, the wave speed is

Answer:
The answer is 1.87nm/s.
Explanation:
The
water loss must be replaced by
of sap. 110g of sap corresponds to a volume of

thus rate of sap replacement is

The volume of sap in the vessel of length
is
,
where
is the cross sectional area of the vessel.
For 2000 such vessels, the volume is

taking the derivative of both sides we get:

on the left-hand-side
is the velocity
of the sap, and on right-hand-side
; therefore,

and since the cross-sectional area is
;
therefore,

solving for
we get:


which is the upward speed of the sap in each vessel.