Answer:
The pencil is not pulled towards a person due to a very small magnitude of force between them, due to lighter masses.
Explanation:
Let us apply Newton's Law of Gravitation between a person and pencil.
Average Mass of a Normal Pencil = m₁ = 10 g = 0.01 kg
Average Mass of a Person = m₂ = 80 kg
Distance between both = r = 1 cm = 0.01 m (Taking minimal distance)
Gravitational Constant = G = 6.67 x 10⁻¹¹ N.m²/kg²
So,
F = Gm₁m₂/r²
F = (6.67 x 10⁻¹¹ N.m²/kg²)(0.01 kg)(80 kg)/(0.01 m)²
<u>F = 5.34 x 10⁻⁷ N</u>
This Force is very small in magnitude due to the light masses of both objects.
<u>Therefore, the pencil is not pulled towards a person due to a very small magnitude of force between them, due to lighter masses.</u>
To solve this problem, we must take two important steps. First we will convert all the given units, to international system. Later we will define the torque, which is given as the product between the radius of application of the force and the Force acting on the body. Mathematically the latter is,

Here,
r = Radius
F = Force
Now the units,

Replacing,


Therefore the torque that the muscle produces on the wrist is 
The tires deflated and so that means that you won’t be able to travel
Answer: K.E = 0.4 J
Explanation:
Given that:
M = 1.0 kg
h = 0.04 m
K.E = ?
According to conservative of energy
K.E = P.E
K.E = mgh
K.E = 1 × 9.81 × 0.04
K.E = 0.3924 Joule
The kinetic energy of the pendulum at the lowest point is 0.39 Joule
Answer:
460.52 s
Explanation:
Since the instantaneous rate of change of the voltage is proportional to the voltage in the condenser, we have that
dV/dt ∝ V
dV/dt = kV
separating the variables, we have
dV/V = kdt
integrating both sides, we have
∫dV/V = ∫kdt
㏑(V/V₀) = kt
V/V₀ = 
Since the instantaneous rate of change of the voltage is -0.01 of the voltage dV/dt = -0.01V
Since dV/dt = kV
-0.01V = kV
k = -0.01
So, V/V₀ = 
V = V₀
Given that the voltage decreases by 90 %, we have that the remaining voltage (100 % - 90%)V₀ = 10%V₀ = 0.1V₀
So, V = 0.1V₀
Thus
V = V₀
0.1V₀ = V₀
0.1V₀/V₀ = 
0.1 = 
to find the time, t it takes the voltage to decrease by 90%, we taking natural logarithm of both sides, we have
㏑(0.01) = -0.01t
So, t = ㏑(0.01)/-0.01
t = -4.6052/-0.01
t = 460.52 s