Answer: The given statement is false.
Explanation:
According to Newton's third law of motion, every action has an equal and opposite reaction. So, when we apply force in one direction on an object then the object also applies a force in the opposite direction.
Hence, it is true that two forces in each pair of forces act in opposite directions.
For example, when we push a wooden box of 20 kg in the forward direction then the box will also apply a force in the opposite direction.
But the statement two forces in each pair can either both act on the same body or they can act on different bodies is false.
Answer:
Explanation:
Let the intensity of unpolarised light be I₀ . After passing through the first polarising filter , the intensity is I₀ / 2 .
After second filter , the intensity will be I₀ / 2 x cos²45 = I₀ / 4
After third filter , the intensity will be I₀ / 4 x cos²45 = I₀ / 8 .
So,
1 / 8 the of initial light passes through the last filter .
Answer:
20.60 kV
Explanation:
Capacitance of parallel plates without dielectric between them is:

with d the distance between the plates, A the area of the plates and ε₀ the constant
, so :

But the dielectric constant is defined as:

With C the effective capacitance (with the dielectric) and Co the original capacitance (without the dielectric). So, the new capacitance is:

But capacitance is related with voltage by:

with Q the charge and V the voltage, using the new capacitance and solving for V:


1). A radio EM wave has a frequency somewhere between 10 KHz and 300 GHz, whereas a visible light EM wave has a frequency somewhere between 428,000 GHz and 790,000 GHz.
2). A radio EM wave has a wavelength somewhere between 1 mm and 30 km, whereas a visible light EM wave has a wavelength somewhere between 380-700 nanometers.