Answer:
1.045 m from 120 kg
Explanation:
m1 = 120 kg
m2 = 420 kg
m = 51 kg
d = 3 m
Let m is placed at a distance y from 120 kg so that the net force on 51 kg is zero.
By use of the gravitational force
Force on m due to m1 is equal to the force on m due to m2.



3 - y = 1.87 y
3 = 2.87 y
y = 1.045 m
Thus, the net force on 51 kg is zero if it is placed at a distance of 1.045 m from 120 kg.
Answer:

Explanation:
If we assume that the Earth is a spherical conductor, according to Gauss's Law, the electric field is given by:

Here k is the Coulomb constant, the excess charge on the Earth's surface and r its radius. Solving for q:

Space telescopes must be placed in orbit around earth in order to observe short-wavelength radiation.
<h3>What is telescope?</h3>
A telescope is an optical instrument that uses lenses, curved mirrors, or a combination of both to watch distant objects.
When atoms in a gas reach this temperature, they travel so quickly that when they collide, they release X-ray photons with wavelengths smaller than 10 nanometers.
Because the Earth's atmosphere prevents all X-rays from space, these wavelengths must be seen using space telescopes.
To study short-wavelength radiation, space telescopes must be put in orbit around the Earth.
Hence, space telescope is the correct answer.
To learn more about the telescope, refer:
brainly.com/question/556195
#SPJ1
C. It depends on the medium
The answer is true because A current carrying wire is surrounded by magnetic field