Answer: Open system
According to thermodynamics, if a system exchanges matter and energy with its environment it is an open system. For example, human beings and animals can be considered as open systems, since we take chemical energy in the form of food and perform work on our surrounding environment when moving and doing activities.
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The basic unit that represents the quantum nature of electricity is the charge of the electron, represented with the symbols

, which corresponds to

The quantum nature of electricity was demonstrated for the first time by Millikan, in its oil drop experiment. In this experiment, Millikan put charged oil drops between two metallic plates, applying a potential difference across them, such that the electrical force acting on the drops was in balance with their weight. Knowing the intensity of the electric field and the mass of the drops, he was able to determine the charge of the oil drops, and he found that this charge was always an integer multiple of a certain value, exactly

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The non-relativistic formula for low speed v < 0.1c is:
K.E = 0.5mv^2 = 0.5 * 235 * (7)^2 = 5757.5 J
Answer:
0.68 seconds
Explanation:
Data provided in the question:
Mass of the box = 50 kg
Speed of the box = 1.0 m/s
Coefficient of friction, μ = 0.15
Now,
Force applied = μmg
Here,
g is the acceleration due to gravity = 9.8 m/s²
Thus,
F = 0.15 × 50 × 9.8
= 73.5 N
Also,
Force = Mass × Acceleration
thus,
73.5 N = 50 × a
or
a = 1.47 m/s²
After doubling the speed
Final speed = 2 × Initial speed
= 2 × 1 m/s
= 2 m/s
Also,
Acceleration = [change in speed] ÷ Time
or
1.47 = [ 2 - 1 ] ÷ Time
or
Time = 1 ÷ 1.47
or
Time = 0.68 seconds
Answer:

Explanation:
The torque of a force is given by:

where
F is the magnitude of the force
d is the distance between the point of application of the force and the centre of rotation of the system
is the angle between the direction of the force and d
In this problem, we have:
, the force
, the distance of application of the force from the centre (0,0)
, the angle between the direction of the force and a
Therefore, the torque is
