The universal law of gravitation states that:
Every object in the universe attracts every other object with a force which is proportional to the product of their masses and inversely proportional to the square of distance between them.
It means that if the gravitational force is F, then if the distance is decreased by 5 times, then the new gravitation force is:
F/5² = F/25
Answer:
Distance = 3.69 × 10^9 m
The distance from the probe to Earth is 3.69 × 10^9 m
Explanation:
Distance from the probe to the Earth can be derived using the simple motion formula;
Distance = speed × time .....1
Since a radio signal uses an electromagnetic wave to transfer signal, it has the same speed as the speed of light.
Speed of radio signal = speed of light = 3.0 × 10^8 m/s
time taken to reach the earth = 12.3 seconds
Substituting the values of speed and time into equation 1;
Distance = 3.0 × 10^8 m/s × 12.3 s
Distance = 36.9 × 10^8 m
Distance = 3.69 × 10^9 m
Note: all electromagnetic radiation have the same speed which is equal to 3.0 × 10^8 m/s
Electric potential = work done/charge of electron = 2.18×10⁻¹⁸/1.6×10⁻¹⁹
= 13.625 V
Answer:
A) magnitude = sqrrt(147.1^2 + 61^2) = 159.2 units
B)22.5° (clockwise form -ve X axis)
Explanation:
given vector = V1 = x i - 60 j
magnitude of V1 = 90
x - component can be found out by resultant formula
90^2 = x^2 + (-60)^2
x = 67.08 = 67.1 units (3sf)
FOR THE VECTOR 80 UNITS IN -VE X DIRECTION
The X component is -80-------(1)
The Y component is 0 ---------(2)
<u>For the x- component of new added vector:</u>
(1)----------- x + 67.1 = -80
x = -147.1 = -147.1
<u>For the y- component of new added vector:</u>
<u>(</u>2)---------- y - 61 = 0
y = 61.0 (3sf)
the new added vector is = -147.1 i + 61 j
magnitude = sqrrt(147.1^2 + 61^2) = 159.2 units
direction = arctan (61 / 147.1)
= 22.5° (clockwise form -ve X axis)
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Answer:
B) Within an atom, an electron can have only particular energies.
Explanation:
As we know that electrons have energy but apart from electrons we know that protons and neutrons inside the nucleus of atom will also have energy in them.
rest all the statements are true as we have
A) Electrons orbit the nucleus rather like planets orbiting the Sun.
TRUE, because electrons can move in stationary orbit around the nucleus
C) Electrons can jump between energy levels in an atom only if they receive or give up an amount of energy equal to the difference in energy between the energy levels.
Difference amount of energy is lost or absorbed by the electron in form of photons
D) An electron has a negative electrical charge.
Charge of an electron is given as 
E) Electrons have very little mass compared to protons or neutrons
Mass of an electron is given as
mass of proton or neutron
