by the concept of momentum conservation we can say
if net force on a system of mass is ZERO then its momentum will remain conserved
Here a ball is projected upwards so if we take Ball + Earth as a system then total momentum of the system will remain conserved
Initially when ball is on the surface of earth the system has zero momentum and hence we can say after throwing the ball momentum of earth + ball must be zero
now using same equation we can say
given that
from above equation velocity of earth will be
so above will be the recoil speed of earth
The correct answer is a, lunar eclipse
I think the answer is B but i could be wrong
Answer:
q = 7.4 10⁻¹⁰ C
Explanation:
a) The magnetic force is given by the expression
F = q v x B
Where the blacks indicate vectors, q is the electric charge, v at particle velocity and B the magnitude of the magnetic field. If the velocity is perpendicular to the magnetic field, the sine is 1
F = q v B
Let's calculate the charge
q = F / vB
q = 1.00 10⁻¹² / 30.0 B
For the magnetic field of the earth we have a value between 25μT and 65μT, an intermediate value would be 45 μT, let's use this value.
q = 1 10⁻¹² / (30 45 10⁻⁶)
q = 7.4 10⁻¹⁰ C
b) In laboratories and modern electronics, currents of up to 1 10⁻⁶ A can be achieved without much difficulty, in advanced and research laboratories currents of up to 1 10⁻¹² can be managed. Load values (coulomb) cannot they are widely used today for work, but 1 mA = 3.6C, so we see that getting loads with the value of 10⁻¹⁰ C implies very small current less than 1 10⁻¹³ A, which only in laboratories of Very specialized can be created. Consequently, from the above it would be difficult to find loads lower than the calculated
The electrostatic charge is the one created by the friction between two surfaces, it is an indicated charge, in this case it would be possible to have better wing loads found from 10⁻¹⁰C
Density = (mass) / (volume), no matter how large or small the sample is.
We can't calculate the density, because you left out the number for the volume.
Also, you didn't tell us the unit for the mass of 180.
a). If the mass is 180 grams, then the density is
(180 gm) / (volume) .
b). No matter how many pieces you crush it into, and
no matter how large or small a piece is, its density is
the same. (I just wish we knew what the density really is.)
c). A piece may have 80 grams of mass. It doesn't "weigh" 80 grams.
Since the density of the whole rock is (180 gm) / (volume),
the density of any piece of it is (180 gm) / (volume).
Multiply each side by (volume): (Density) x (volume) = 180 gm
Divide each side by (density): Volume = (180 gm) / (density)
We can't calculate the volume of an 80-gm piece, because
we don't know the density. (That's because you left the volume
out of the question.)
