Answer:
the ans is D... good luck
Gravity is a pair of forces of attraction between every
two objects. Period !
It doesn't matter whether they're moving together, moving apart,
moving gracefully in synchrony, or at rest. The gravitational forces
of attraction between them are always there.
Answer:
Ratio of magnetic field will be 
Explanation:
We have given radius of the loop r = 30 mm = 0.03 m
We know that magnetic field at the center of the loop is given by
---------eqn 1
Number of turns in the solenoid is given as n = 3 turn per mm = 3000 turn per meter
We know that magnetic field due to solenoid is given by
-------------eqn 2
Now dividing eqn 1 by eqn 2

The propagation errors we can find the uncertainty of a given magnitude is the sum of the uncertainties of each magnitude.
Δm = ∑
Physical quantities are precise values of a variable, but all measurements have an uncertainty, in the case of direct measurements the uncertainty is equal to the precision of the given instrument.
When you have derived variables, that is, when measurements are made with different instruments, each with a different uncertainty, the way to find the uncertainty or error is used the propagation errors to use the variation of each parameter, keeping the others constant and taking the worst of the cases, all the errors add up.
If m is the calculated quantity, x_i the measured values and Δx_i the uncertainty of each value, the total uncertainty is
Δm = ∑
| dm / dx_i | Dx_i
for instance:
If the magnitude is a average of two magnitudes measured each with a different error
m =
Δm = |
| Δx₁ + |
| Δx₂
= ½
= ½
Δm =
Δx₁ + ½ Δx₂
Δm = Δx₁ + Δx₂
In conclusion, using the propagation errors we can find the uncertainty of a given quantity is the sum of the uncertainties of each measured quantity.
Learn more about propagation errors here:
brainly.com/question/17175455
Possibilities . . .
-- nuclear reaction
-- nuclear fission
-- nuclear fusion
-- radioactive decay.
Any of these makes it a true statement.