The electric field strength is inversely related to the square of the distance.so the strength of the electric field is given by

Here,
is constant depend upon medium and its value is
and q is charge and r is the distance.
Given
and we know the charge of proton,
.
Therefore,

31.3m/s
Explanation:
Given parameters:
Mass of rock = 40kg
Height of cliff = 50m
Unknown:
Speed of rock when it hits ground = ?
Solution:
We are going to use the appropriate motion equation to solve this problem
The rock is falling with the aid of gravitational force. The force is causing it to accelerate with an amount of velocity.
Using;
V² = U² + 2gH
V = unknown velocity
U = initial velocity = O
g = acceleration due to gravity = 9.8m/s²
H = height of fall
since the initial velocity of the bodyg is 0
V² = 2gH
V= √2gH = √2 x 9.8 x 50 = 31.3m/s
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Velocity brainly.com/question/4460262
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Answer:
Based on its mass, the sun's gravitational attraction to the Earth is more than 177 times greater than that of the moon to the Earth.
The period of a simple pendulum is given by:

where L is the pendulum length, and g is the gravitational acceleration of the planet. Re-arranging the formula, we get:

(1)
We already know the length of the pendulum, L=1.38 m, however we need to find its period of oscillation.
We know it makes N=441 oscillations in t=1090 s, therefore its frequency is

And its period is the reciprocal of its frequency:

So now we can use eq.(1) to find the gravitational acceleration of the planet:
The acceleration due to gravity is given as:
g = GM/r²
<h3>
Derivation of gravitational acceleration:</h3>
According to Newton's second law of motion,
F = ma
where,
F = force
m = mass
a = acceleration
According to Newton's law of gravity,
F<em>g </em>= GMm/(r + h)²
F<em>g = </em>gravitational force
From Newton's second law of motion,
F<em>g </em>= ma
a = F<em>g</em>/m
We can refer to "a" as "g"
a = g = GMm/(m)(r + h)²
g = GM/(r + h)²
When the object is on or close to the surface, the value of g is constant and height has no considerable impact. Hence, it can be written as,
g = GM/r²
Learn more about gravitational acceleration here:
brainly.com/question/2142879
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