Answer:
c. Moon A is four times as massive as moon B
Explanation:
Let's assume the:
- mass of the object =

- mass of the moon A =

- mass of the moon B =

- distance between the center of masses of the object and moon B =

According to the given condition the object is twice as far from moon A as it is from moon B
- ∴distance between the center of masses of the object and moon B =

<u>As we know, gravitational force of attraction is given by:</u>

<em>According to the condition</em>
Force on m due to
Force on m due to



I had the same question on a test, the answer is A. Both solar and hydroelectric energy do not emit air pollutants, and although geothermal energy releases some gases, biomass is the biggest polluter.<span>
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Answer:
a) 
b) 
Explanation:
The frequency of the
harmonic of a vibrating string of length <em>L, </em>linear density
under a tension <em>T</em> is given by the formula:

a) So for the <em>fundamental mode</em> (n=1) we have, substituting our values:

b) The <em>frequency difference</em> between successive modes is the fundamental frequency, since:

Answer:
Minimum number of photons required is 1.35 x 10⁵
Explanation:
Given:
Wavelength of the light, λ = 850 nm = 850 x 10⁻⁹ m
Energy of one photon is given by the relation :
....(1)
Here h is Planck's constant and c is speed of light.
Let N be the minimum number of photons needed for triggering receptor.
Minimum energy required for triggering receptor, E₁ = 3.15 x 10⁻¹⁴ J
According to the problem, energy of N number of photons is equal to the energy required for triggering, that is,
E₁ = N x E
Put equation (1) in the above equation.

Substitute 3.15 x 10⁻¹⁴ J for E₁, 850 x 10⁻⁹ m for λ, 6.6 x 10⁻³⁴ J s for h and 3 x 10⁸ m/s for c in the above equation.

N = 1.35 x 10⁵